U.S. patent number 6,800,684 [Application Number 10/142,946] was granted by the patent office on 2004-10-05 for composite particles, and tread rubber composition, paint and resin composition using the same.
This patent grant is currently assigned to Toda Kogyo Corporation. Invention is credited to Kazuyuki Hayashi, Keisuke Iwasaki, Hiroko Morii, Mineko Ohsugi, Yusuke Shimohata.
United States Patent |
6,800,684 |
Hayashi , et al. |
October 5, 2004 |
Composite particles, and tread rubber composition, paint and resin
composition using the same
Abstract
Composite particles capable of an excellent dispersibility and
an excellent light resistance of the present invention have an
average particle diameter of 0.001 to 12.0 .mu.m, comprise: white
inorganic particles as core particles; a gluing agent-coating layer
formed on at least a parts of the surface of said white inorganic
particle; and a black pigment coat composed of carbon black,
aniline black or both carbon black and aniline black, formed onto
at least a part of the gluing agent-coating layer in an amount of
from 1 to 500 parts by weight based on 100 parts by weight of said
white inorganic particles.
Inventors: |
Hayashi; Kazuyuki (Hiroshima,
JP), Morii; Hiroko (Hiroshima, JP),
Iwasaki; Keisuke (Hiroshima, JP), Ohsugi; Mineko
(Hiroshima, JP), Shimohata; Yusuke (Hiroshima,
JP) |
Assignee: |
Toda Kogyo Corporation
(Hiroshima-ken, JP)
|
Family
ID: |
27346721 |
Appl.
No.: |
10/142,946 |
Filed: |
May 13, 2002 |
Foreign Application Priority Data
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May 16, 2001 [JP] |
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2001-146940 |
Nov 14, 2001 [JP] |
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2001-348147 |
Nov 27, 2001 [JP] |
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2001-360293 |
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Current U.S.
Class: |
524/442; 523/210;
523/215; 523/214; 523/216; 524/445; 524/446; 524/430 |
Current CPC
Class: |
C09C
1/309 (20130101); C09D 7/62 (20180101); C08K
9/02 (20130101); C09C 1/043 (20130101); C09C
1/3692 (20130101); C09D 7/67 (20180101); C09D
7/68 (20180101); C08K 9/02 (20130101); C08L
21/00 (20130101); C01P 2006/12 (20130101); C08K
9/06 (20130101); C01P 2004/62 (20130101); C08K
3/22 (20130101); C01P 2006/40 (20130101); C08K
3/36 (20130101) |
Current International
Class: |
C09C
1/30 (20060101); C08K 9/00 (20060101); C09C
1/04 (20060101); C08K 9/02 (20060101); C09D
7/12 (20060101); C09C 1/28 (20060101); C09C
1/36 (20060101); C08K 003/34 (); C08K 009/12 () |
Field of
Search: |
;524/492,430,495,496,437
;523/214,215,210,216 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 913 431 |
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May 1999 |
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EP |
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743630 |
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Jan 1956 |
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GB |
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Primary Examiner: Cain; Edward J.
Assistant Examiner: Wyrozebski; Katarzyna
Attorney, Agent or Firm: Nixon & Vanderhye P.C.
Claims
What is claimed is:
1. Composite particles having an average particle diameter of 0.001
to 12.0 .mu.m, comprising: white inorganic particles as core
particles; a gluing agent-coating layer formed on at least a parts
of the surface of said white inorganic particle; and a black
pigment coat composed of carbon black, aniline black or both carbon
black and aniline black, formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of said white inorganic particles.
2. Composite particles according to claim 1, wherein said composite
particles have a BET specific surface area value of 0.5 to 500
m.sup.2 /g.
3. Composite particles according to claim 1, wherein a coating
layer comprising at least one compound selected from the group
consisting of hydroxides of aluminum, oxides of aluminum,
hydroxides of silicon and oxides of silicon, is disposed between
the surface of the respective white inorganic particle and the
gluing agent-coating layer.
4. Composite particles according to claim 3, wherein the amount of
the coating layer comprising at least one compound selected from
the group consisting of hydroxides of aluminum, oxides of aluminum,
hydroxides of silicon and oxides of silicon, is 0.01 to 20% by
weight, calculated as Al, SiO.sub.2 or a sum of Al and SiO.sub.2,
based on the weight of the white inorganic particles.
5. Composite particles according to claim 1, wherein said white
inorganic particles are (1) silica particles, (2) white inorganic
particles having a refractive index of less than 2.0, or (3) white
inorganic particles having a refractive index of not less than
2.0.
6. Composite particles according to claim 5, wherein said silica
particles are anhydrous silicic acid powder, hydrous silicic acid
powder, silicate powder or silica gel.
7. Composite particles according to claim 5, wherein said white
inorganic particles (2) having a refractive index of less than 2.0
are anhydrous silicic acid powder, hydrous silicic acid powder and
silicate powder, silica gel, diatomaceous earth powder clay,
calcium carbonate, barium sulfate, talc or alumina white.
8. Composite particles according to claim 5, wherein said white
inorganic particles (3) having a refractive index at not less than
2.0 are titanium oxide particles or zinc oxide particles.
9. Composite particles according to claim 1, wherein said composite
particles are composite silica particles (1) having an average
particle diameter of 0.001 to 0.6 .mu.m and comprising silica
particles as core particles; a coating layer formed on at least a
part of the surface of the silica particles, comprising
organosilane compounds obtainable from alkoxysilanes, or
polysiloxanes; and a carbon black coat formed on at least a part of
the surface of the coating layer in an amount of 1 to 500 parts by
weight based on 100 parts of the silica particles.
10. Composite particles according to claim 9, further comprising an
outer surface coat comprising a fatty acid, a metal salt of fatty
acid or a coupling agent.
11. Composite particles according to claim 10, wherein the amount
of the outer surface coat comprising a fatty acid, a metal salt of
fatty acid or a coupling agent is 0.1 to 10.0% by weight,
calculated as C, based on the weight of the composite
particles.
12. Composite particles according to claim 1, wherein said
composite particles are composite particles having an average
particle diameter of 0.001 to 12.0 .mu.m and comprising white
inorganic particles having a refractive index of less than 2.0 as
core particles; the gluing agent-coating layer formed on at least a
part of the surface of the white inorganic particle; and a black
pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
composed of carbon black, aniline black or both carbon black and
aniline black.
13. Composite particles according to claim 12, wherein said
composite particles have a BET specific surface area value of 0.5
to 500 m.sup.2 /g, a blackness (L* value) of 14.5 to 30.0, a black
pigment desorption percentage of not more than 20%, and a repose
angle of not more than 45.degree..
14. Composite particles according to claim 1, wherein said
composite particles are composite particles having an average
particle diameter of 0.001 to 12.0 .mu.m and comprising white
inorganic particles having a refractive index of not less than 2.0
as core particles; the gluing agent-coating layer formed on at
least a part of the surface of the white inorganic particle; and a
black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
comprising carbon black, aniline black or carbon black and aniline
black.
15. Composite particles according to claim 14, wherein said
composite particles have a Bet specific surface area value of 0.5
to 500 m.sup.2 /g, a blackness (L* value) of 14.5 to 90.0, a black
pigment desorption percentage of not more than 20%, and a repose
angle of not more than 4.degree..
16. A pigment comprising composite particles defined in claim
1.
17. A tread rubber composition, comprising: 100 parts by weight of
a rubber component; and 10 to 200 parts by weight of the pigment
composed of the composite particles defined in claim 9.
18. A tread rubber composition according to claim 17, wherein said
tread rubber composition has a volume resistivity value of not more
than 1.0.times.10.sup.5 .OMEGA..multidot.cm, a tensile strength of
not less than 23.0 MPa, and a light resistance (.DELTA.E* value) of
not more than 5.0.
19. A paint comprising: said pigment composed of the composite
particles defined in claim 12; and a paint base material.
20. A paint according to claim 19, wherein the amount of said
composite particles is 0.5 to 100 parts by weight based on 100
parts by weight of said paint base material.
21. A rubber or resin composition comprising: said pigment composed
of the composite particles defined in claim 12; and a base material
for rubber or resin composition.
22. A rubber or resin composition according to claim 21, wherein
the amount of said composite particles is 0.5 to 200 parts by
weight based on 100 parts by weight of said base material for
rubber or resin composition.
Description
BACKGROUND OF THE INVENTION
The present invention relates to composite particles, and a tread
rubber composition, a paint and a resin composition using the
composite particles, and more particularly, to composite particles
capable of an excellent dispersibility and an excellent light
resistance; a tread rubber composition prepared by blending the
composite particles in rubber, which can show a less discoloration
upon exposure to light, a low electric resistance, an excellent
wear resistance and an excellent tensile strength; and a paint
containing the composite particles and a resin composition
containing the composite particles.
The composite particles of the present invention can be used as
pigments, or colorants, fillers or the like for rubbers, paints and
resin compositions.
As white inorganic particles having a refractive index of less than
2.0, there are generally known extender pigments. The extender
pigments form a transparent or translucent dispersion when
dispersed in vehicles such as oils and varnishes. Therefore, the
extender pigments have been conventionally used as non-color
pigments, i.e., as extenders for paints, printing inks or the like.
With the progress of powder science or technology, the extender
pigments have been recently used not only as extenders, but also as
function-imparting pigments in extensive industrial fields for the
purpose of controlling or improving the processability and physical
properties of rubbers, plastics, paints, printing inks, adhesives,
sealing materials, papers or the like.
However, although the extender pigments show transparency or
translucency in vehicle, paints or resin compositions to which the
extender pigments are added as fillers, exhibit a more whitish
color than those containing no extender pigments, and fail to show
a sufficient blackness required in some application fields.
White inorganic particles having a refractive index of not less
than 2.0 such as titanium oxide, zinc oxide and zirconium oxide,
have been conventionally used as white pigments for rubbers,
plastics, paints or printing inks.
In particular, it is known that titanium oxide and zinc oxide
exhibit an ultraviolet light-shielding effect because these
pigments can absorb light in ultraviolet region. In recent years,
the titanium oxide and zinc oxide are also used as an ultraviolet
light absorber for cosmetics or the like.
However, it is also known that the titanium oxide and zinc oxide
have a high surface activity. Therefore, when paints or resin
compositions using these pigments are exposed to outdoor
environments, there arise problems such as chalking of a painted
surface and deterioration of resins.
In addition, white inorganic particles are generally
non-conductive, for example, silica particles and zinc oxide have
volume resistivity values of about 10.sup.6 to 10.sup.8
.OMEGA..multidot.cm and about 10.sup.7 .OMEGA..multidot.cm,
respectively. Therefore, it is known that in the applications
requiring a higher or lower volume resistivity value, it is
necessary to use an electric resistance-regulating agent such as
carbon black or the like in addition to the white inorganic
particles.
On the other hand, black pigments such as aniline black, carbon
black or the like have been extensively used in various
applications such as inks, paints, rubbers and plastics for the
purpose of imparting thereto a tinting property, electric
properties, a light-absorbing property or the like.
However, it is known that these black pigments, especially carbon
black, are fine particles having an average particle diameter as
small as about 0.005 to 0.05 .mu.m and, therefore, it is difficult
to disperse carbon black in vehicles or resin compositions. In
addition, it is also known that these black pigments are bulky
particles having a bulk density as high as about 0.1 g/cm.sup.3
and, therefore, are deteriorated in handling property and
workability.
Further, since the paints or resin compositions using such black
particles are sometimes used in outdoor applications and exposed to
direct sunlight or severe weather conditions such as winds and
rains, the black particles are required to maintain a good hue and
properties thereof for a long period of time, namely to show
excellent light resistance and weather resistance.
Consequently, it has been strongly required to provide black
particles capable not only imparting thereto various properties
such as electric properties, ultraviolet light-absorbing property
or the like according to applications thereof, but also exhibiting
excellent light resistance, tinting strength and dispersibility in
vehicle.
Hitherto, it is known that silica particles are blended together
with carbon black in rubbers for the purposes of reduction in
electric resistance of the rubbers as well as reinforcement thereof
(Japanese Patent Application Laid-Open (KOKAI) No. 52-93452(1977),
and Japanese Patent Nos. 2722077, 2788212 and 3160552).
In addition, it is also known that titanium oxide or zinc oxide is
coated with a silica-based substance in order to suppress the
surface activity (Japanese Patent Application Laid-Open (KOKAI)
Nos. 2000-319128 and 2001-58821).
At present, it has been strongly required to provide composite
particles capable of not only imparting thereto various properties
such as electric properties, ultraviolet light-shielding property,
according to the applications thereof, but also exhibiting
excellent light resistance, tinting strength, handling property and
dispersibility in vehicle. However, conventional composite
particles have failed to satisfy all of these requirements.
Namely, in Japanese Patent Application Laid-Open (KOKAI) No.
52-93452(1977) and Japanese Patent Nos. 2722077 and 3160552, there
are described carbon-coated silica particles and a rubber
composition containing such coated silica particles which are used
for tires. However, in any of these, since a carbon black coat is
formed on the surface of the silica particle by thermal
decomposition of organic compounds, the adhesion of carbon black
onto the surface of the silica particle is very weak. Therefore,
when the coated silica particles are kneaded in the rubber
composition, the carbon black coated is desorbed or fallen-off from
the surface of the silica particle, so that a part of the surface
of the silica particles is exposed. This results in non-uniform
dispersion of the silica particles in the rubber composition, and
failure to exhibit sufficient the above-mentioned effects.
The rubber composition described in Japanese Patent No. 2788212 is
a tire tread rubber composition containing carbon black
surface-treated with 0.1 to 50% by weight of silica. However, the
adhesion of silica onto the surface of carbon black is very weak.
Therefore, when the coated carbon black is kneaded in the rubber
composition, the silica coated thereon is desorbed or fallen-off
from the surface of the carbon black, thereby preventing carbon
black from being uniformly dispersed in the composition.
Also, in Japanese Patent Application Laid-Open (KOKAI) Nos.
2000-319128 and 2001-58821, there is described zinc oxide or
titanium oxide whose surface is coated with silica, silica-based
substances such as alkyl-modified silica, zinc silicate or the
like. However, the coating formed on zinc oxide or titanium oxide
fails to sufficiently reduce the surface activity thereof.
In Japanese Patent Application Laid-Open (KOKAI) Nos.
11-323174(1999) and 2001-11339, there are described iron-based
composite particles comprising black iron oxide particles or black
iron oxide hydroxide particles as core particles, a coating layer
formed on the surface of the core particle which comprises
organosilane compounds obtainable from alkoxysilanes or
polysiloxanes, and a carbon black coat coated onto the surface of
the coating layer composed of organosilane compounds or
polysiloxanes. However, these techniques are related to the method
of fixedly coating carbon black onto the black iron compound
particles. Since the core particles show a magnetism, the obtained
composite particles cannot be used in applications in which such a
magnetism is unnecessary and unsuitable, and tend to suffer from
magnetic agglomeration, resulting in poor dispersibility.
Separately, automobile tires have been required to exhibit a good
road grip property even upon running on a wet road in order to
attain a high running safety, as well as high wear resistance and
high break strength. In recent years, from the standpoints of
saving energy and resources, automobile tires having a low-rolling
resistance for reducing fuel consumption, i.e., so-called low-fuel
consumption tires have been positively developed.
The automobile tires having a high electric resistance tend to
generate noises in radio and electronic devices by undesired static
discharge due to dielectric breakdown, or tend to cause fire by
spark between tire and automobile body due to static
electrification thereof, upon fueling. Therefore, the automobile
tires have been strongly required to exhibit a low electric
resistance.
Conventionally, carbon black is blended in a rubber composition for
tires or the like for the purposes of reinforcement, increase of
wear resistance or reduction of electric resistance. However, it is
known that such carbon black-containing tires have a large rolling
resistance, resulting in large fuel consumption of automobiles.
Consequently, tires in which silica particles capable of reducing a
rolling resistance as compared to carbon black are blended as a
rubber-reinforcing filler, have been proposed and already put into
practice (Japanese Patent Application Laid-Open (KOKAI) No.
3-239737(1991)).
However, since the silica particles have a silanol functional group
on the surface thereof and, therefore, tend to be agglomerated
together by hydrogen bonds between the silanol groups, it has been
difficult to uniformly disperse the silica particles in the rubber
composition for tires or the like. In addition, it is known that
the silica particles show a low compatibility with rubbers
ordinarily used for tires because of a hydrophilic property of the
silanol group present on the surface thereof, resulting in poorer
reinforcing effect as compared to carbon black.
In order to improve the dispersibility of the silica particles in
rubbers, there has been proposed the method of treating the surface
of the silica particles with an organosilicon compound (Japanese
Patent Application Laid-Open (KOKAI) No. 8-245838(1996)).
Further, when the silica particles are used as a reinforcing
filler, an electric resistance of tires increase owing to
non-conductivity thereof. Therefore, tires using conductive
particles such as carbon black in combination with the silica
particles have been proposed and already put into practice
(Japanese Patent Application Laid-Open (KOKAI) Nos. 52-93452(1977),
3-239737(1991) and 8-245838(1996), Japanese Patent Nos. 2722077,
2788212 and 3160552, etc.).
Furthermore, ordinary automobile tires are colored black and,
therefore, have been strongly required to exhibit a high blackness
as well as a less discoloration upon exposure to light from the
viewpoint of good appearance.
Also, at present, it has been strongly required to provide a tread
rubber composition exhibiting a less discoloration upon exposure to
light, a low electric resistance, an excellent wear resistance and
an excellent tensile strength. However, conventional tread rubber
compositions have failed to satisfy all of these requirements.
Namely, the tire tread composition described in Japanese Patent
Application Laid-Open (KOKAI) No. 3-239737(1991), comprises 100
parts by weight of a rubber blend containing a styrene-butadiene
copolymer prepared by copolymerizing styrene and butadiene in the
presence of an organolithium compound, in an amount of not less
than 30 parts by weight; 10 to 150 parts by weight of silica
particles; and 0 to 100 parts by weight of carbon black. However,
since the silica particles are non-uniformly dispersed in the
rubber composition, it is difficult to attain excellent wear
resistance and tensile strength. In addition, since the silica
particles prevent carbon black from being uniformly dispersed, it
is difficult to reduce an electric resistance of the obtained
composition.
In Japanese Patent Application Laid-Open (KOKAI) No. 52-93452(1977)
and Japanese Patent Nos. 2722077 and 3160552, as seen from the
above, the adhesion of carbon black to the surface of the silica
particle is very weak (shown below in Comparative Examples).
Therefore, the silica particles are non-uniformly dispersed in the
rubber composition, resulting in deterioration in wear resistance
and tensile strength.
As a result of the present inventors' earnest studies, it has been
found that composite particles having an average particle size of
0.001 to 12.0 .mu.m, which comprise white inorganic particles; a
gluing agent-coating layer formed on at least a part of the surface
of the white inorganic particle, comprising at least one gluing
agent selected from the group consisting of organosilicon
compounds, various coupling agents such as silane-based coupling
agents, titanate-based coupling agents, aluminate-based coupling
agents and zirconate-based coupling agents, oligomer compounds and
polymer compounds; and a black pigment coat composed of carbon
black and/or aniline black, formed on at least a part of the
surface of the coating layer composed of the gluing agent in an
amount of 1 to 500 parts by weight based on 100 parts by weight of
the white inorganic particles, can exhibit an excellent light
resistance and dispersibility. The present invention has been
attained on the basis of the finding.
SUMMARY OF THE INVENTION
An object of the present invention is to provide composite
particles exhibiting an excellent light resistance and an excellent
dispersibility.
An object of the present invention is to provide black composite
particles for a tread rubber composition, which exhibit not only a
high blackness and a less discoloration upon exposure to light, but
also a low volume resistivity value and an excellent
dispersibility
An object of the present invention is to provide black composite
particles for a paint or a resin composition, which is capable of
not only imparting thereto various functions according to
applications thereof, but also exhibiting excellent light
resistance, tinting strength and dispersibility in vehicle.
An object of the present invention is to provide composite
particles for a paint or a resin composition, which is capable of
not only imparting thereto various functions according to
applications thereof, but also exhibiting especially an excellent
ultraviolet light-shielding property as well as excellent light
resistance, handling property and dispersibility in vehicle.
An object of the present invention is to provide a tread rubber
composition capable of exhibiting a less discoloration upon
exposure to light, a low electric resistance, and excellent wear
resistance and tensile strength.
An object of the present invention is to provide a paint or a resin
composition capable of exhibiting a high blackness, a more
excellent light resistance and a more excellent storage
stability.
An object of the present invention is to provide a paint or a resin
composition capable of exhibiting a more excellent light resistance
and a more excellent storage stability.
To accomplish the aims, in a first aspect of the present invention,
there are provided composite particles having an average particle
diameter of 0.001 to 12.0 .mu.m, comprising:
white inorganic particles as core particles;
a gluing agent-coating layer formed on at least a parts of the
surface of said white inorganic particle; and
a black pigment coat composed of carbon black, aniline black or
both carbon black and aniline black, formed onto at least a part of
the gluing agent-coating layer in an amount of from 1 to 500 parts
by weight based on 100 parts by weight of said white inorganic
particles.
In a second aspect of the present invention, there are provided
composite particles having an average particle diameter of 0.001 to
12.0 .mu.m, comprising:
white inorganic particles as core particles;
a coating layer formed on at least a parts of the surface of said
white inorganic particle, comprising at least one compound selected
from the group consisting of hydroxides of aluminum, oxides of
aluminum, hydroxides of silicon and oxides of silicon,
a gluing agent-coating layer formed on at least a parts of the
surface of said coating layer; and
a black pigment coat composed of carbon black, aniline black or
both carbon black and aniline black, formed onto at least a part of
the gluing agent-coating layer in an amount of from 1 to 500 parts
by weight based on 100 parts by weight of said white inorganic
particles.
In a third aspect of the present invention, there are provided
composite particles having an average particle diameter of 0.001 to
0.5 .mu.m, and comprising:
silica particles (1) as core particles;
a coating layer formed on at least a part of the surface of the
silica particles (1), comprising organosilane compounds obtainable
from alkoxysilanes, or polysiloxanes; and
a carbon black coat formed on at least a part of the surface of the
coating layer in an amount of 1 to 500 parts by weight based on 100
parts of the silica particles (1).
In a fourth aspect of the present invention, there are provided
composite particles having an average particle diameter of 0.001 to
0.5 .mu.m, and comprising:
silica particles (1) as core particles;
a coating layer formed on at least a part of the surface of the
silica particles (1), comprising organosilane compounds obtainable
from alkoxysilanes, or polysiloxanes;
a carbon black coat formed on at least a part of the surface of the
coating layer in an amount of 1 to 500 parts by weight based on 100
parts of the silica particles (1); and
an outer surface coat formed on at least a part of the surface of
the carbon black coat, comprising a fatty acid, a metal salt of
fatty acid or a coupling agent.
In a fifth aspect of the present invention, there are provided
composite particles having an average particle diameter of 0.001 to
12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of less than
2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
composed of carbon black, aniline black or both carbon black and
aniline black.
In a sixth aspect of the present invention, there are provided
composite particles having an average particle diameter of 0.001 to
12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of not less
than 2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
comprising carbon black and/or aniline black.
In a seventh aspect of the present invention, there is provided a
pigment comprising composite particles defined in any one of the
first to sixth aspects.
In an eighth aspect of the present invention, there is provided a
tread rubber composition, comprising:
100 parts by weight of a rubber component; and
10 to 200 parts by weight of the pigment composed of composite
particles having an average particle diameter of 0.001 to 0.5
.mu.m, and comprising:
silica particles (1) as core particles;
a coating layer formed on at least a part of the surface of the
silica particles (1), comprising organosilane compounds obtainable
from alkoxysilanes, or polysiloxanes; and
a carbon black coat formed on at least a part of the surface of the
coating layer in an amount of 1 to 500 parts by weight based on 100
parts of the silica particles (1).
In a ninth aspect of the present invention, there is provided a
paint comprising:
a paint base material, and
a pigment composed of (i) composite particles having an average
particle diameter of 0.001 to 12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of less than
2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
composed of carbon black, aniline black or both carbon black and
aniline black,
(ii) composite particles having an average particle diameter of
0.001 to 12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of not less
than 2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
comprising carbon black and/or aniline black.
In a tenth aspect of the present invention, there is provided a
rubber or resin composition comprising:
a base material for rubber or resin composition, and
a pigment composed of (i) composite particles having an average
particle diameter of 0.001 to 12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of less than
2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
composed of carbon black, aniline black or both carbon black and
aniline black,
(ii) composite particles having an average particle diameter of
0.001 to 12.0 .mu.m, and comprising:
white inorganic particles having a refractive index of not less
than 2.0 as core particles;
a gluing agent-coating layer formed on at least a part of the
surface of the white inorganic particle; and
a black pigment coat formed onto at least a part of the gluing
agent-coating layer in an amount of from 1 to 500 parts by weight
based on 100 parts by weight of the white inorganic particles,
comprising carbon black and/or aniline black.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
First, the composite particles according to the present invention
are described.
As the white inorganic particles used as core particles in the
present invention, there may be exemplified (1) silica particles,
(2) white inorganic particles having a refractive index of less
than 2.0, and (3) white inorganic particles having a refractive
index of not less than 2.0.
As the silica particles (1), there may be exemplified particles of
any material containing silica as a main component, e.g., white
carbon such as anhydrous silicic acid powder, hydrous silicic acid
powder and silicate powder, and silica gel. In the consideration of
good dispersibility of the obtained composite particles, among
these materials, anhydrous silicic acid powder and hydrous silicic
acid powder are preferred.
As the white inorganic particles (2) having a refractive index of
less than 2.0, there may be exemplified silica particles such as
white carbon (such as anhydrous silicic acid powder, hydrous
silicic acid powder and silicate powder), diatomaceous earth powder
and silica gel; and extender pigments such as clay, calcium
carbonate, barium sulfate, alumina white and talc.
As the white inorganic particles (3) having a refractive index of
not less than 2.0, there may be exemplified white pigments such as
titanium oxide and zinc oxide.
The white inorganic particles may be particles having any suitable
shape, such as spherical particles, granular particles, polyhedral
particles, acicular particles, spindle-shaped particles, rice
grain-shaped particles, flake-shaped particles, scale-like
particles, plate-shaped particles and amorphous particles. The
shape of the silica particles (1) for the tread rubber composition
is preferably spherical or granular.
The particle size of the white inorganic particles may be
appropriately determined according to the applications thereof, and
the average particle diameter of the white inorganic particles is
usually 0.0009 to 12.0 .mu.m.
More specifically, the silica particles (1) for the tread rubber
composition have an average particle diameter of preferably 0.001
to 0.50 .mu.m, more preferably 0.002 to 0.45 .mu.m. still more
preferably 0.003 to 0.40 1 .mu.m.
When the average particle diameter of the silica particles (1) for
the tread rubber composition is more than 0.50 .mu.m, the obtained
composite particles may become coarse particles and, therefore,
tend to be deteriorated in dispersibility in the tread rubber
composition. When the average particle diameter of the silica
particles (1) for the tread rubber composition is less than 0.001
.mu.m, such particles may tend to be agglomerated together by the
increase of intermolecular force therebetween due to fine
particles, so that it may be difficult to form a uniform coating
layer composed of the gluing agent, for example, alkoxysilanes or
polysiloxanes on the surface of the silica particles, and uniformly
coat carbon black on the coating layer composed of the gluing
agent.
The white inorganic particles (2) having a refractive index of less
than 2.0 and the white inorganic particles (3) having a refractive
index of not less than 2.0 have an average particle diameter of
usually 0.0009 to 12.0 .mu.m, preferably 0.0014 to 11.0 .mu.m, more
preferably 0.0019 to 10. 0 .mu.m.
When the average particle diameter of the white inorganic particles
(2) having a refractive index of less than 2.0 and the white
inorganic particles (3) having a refractive index of not less than
2.0 is more than 12.0 .mu.m, the obtained composite particles
become coarse particles and, therefore, may tend to be deteriorated
in tinting strength.
The white inorganic particles of the present invention have a BET
specific surface area value of usually not less than 0.1 m.sup.2
/g.
More specifically, the silica particles (1) for the tread rubber
composition have a BET specific surface area value of preferably
not less than 20 m.sup.2 /g. When the BET specific surface area
value is less than 20 m.sup.2 /g, the silica particles may tend to
be coarse, or sintering may tend to be caused within or between the
silica particles, so that the obtained composite particles also
tend to be coarse and, therefore, tend to be deteriorated in
dispersibility in the tread rubber composition. In the
consideration of good dispersibility in the tread rubber
composition, the BET specific surface area value of the silica
particles (1) for the tread rubber composition is more preferably
not less than 25 m.sup.2 /g, still more preferably not less than 30
m.sup.2 /g. In the consideration of forming a uniform coating layer
composed of the gluing agent, for example, alkoxysilanes or
polysiloxanes on the surface of the silica particles, or uniformly
coating carbon black onto the surface of the coating layer composed
of the gluing agent, the upper limit of the BET specific surface
area value of the silica particles (1) for the tread rubber
composition is preferably 500 m.sup.2 /g, more preferably 400
m.sup.2 /g, still more preferably 300 m.sup.2 /g.
The white inorganic particles (2) having a refractive index of less
than 2.0 and the white inorganic particles (3) having a refractive
index of not less than 2.0 respectively have a BET specific surface
area value of usually not less than 0.1 m.sup.2 /g. When the BET
specific surface area value is less than 0.1 m.sup.2 /g, the white
inorganic particles (2) having a refractive index of less than 2.0
and the white inorganic particles (3) having a refractive index of
not less than 2.0 tend to become coarse, or sintering tend to be
caused within or between the white inorganic particles, so that the
obtained composite particles also tend to become coarse and,
therefore, tend to be deteriorated in tinting strength. In the
consideration of good tinting strength of the obtained composite
particles, the BET specific surface area value of each of the white
inorganic particles (2) having a refractive index of less than 2.0
and the white inorganic particles (3) having a refractive index of
not less than 2.0 is preferably not less than 0.3 m.sup.2 /g, more
preferably not less than 0.5 m.sup.2 /g. In the consideration of
forming a uniform gluing agent-coating layer on the surface of the
white inorganic particles (2) having a refractive index of less
than 2.0 and the white inorganic particles (3) having a refractive
index of not less than 2.0, or uniformly coating the black pigments
onto the surface of the coating layer composed of the gluing agent,
the upper limit of the BET specific surface area value of each of
the white inorganic particles (2) having a refractive index of less
than 2.0 and the white inorganic particles (3) having a refractive
index of not less than 2.0 is usually 500 m.sup.2 /g, preferably
400 m.sup.2 /g, more preferably 300 m.sup.2 /g.
The silica particles (1) have a volume resistivity value of usually
not less than 1.0.times.10.sup.5 .OMEGA..multidot.cm.
As to the hue of each of the white inorganic particles (2) having a
refractive index of less than 2.0 and the white inorganic particles
(3) having a refractive index of not less than 2.0, the L* value
thereof is usually not less than 70.00, preferably not less than
75.00, and the C* value thereof is usually not more than 18.00,
preferably not more than 15.00, more preferably not more than
12.00. When the L* value and C* value are out of the
above-specified ranges, the white inorganic particles fail to show
a sufficient white color, so that it may be difficult to obtain the
aimed composite particles of the present invention.
The refractive index of the white inorganic particles (2) having a
refractive index of less than 2.0, is more preferably not more than
1.9, still more preferably not more than 1.8 in the consideration
of the blackness of the obtained composite particles.
As to the light resistance of each of the white inorganic particles
(2) having a refractive index of less than 2.0 and the white
inorganic particles (3) having a refractive index of not less than
2.0, the lower limit of the .DELTA.E* value thereof is usually more
than 5.0, and the upper limit of the .DELTA.E* value thereof is
usually 12.0, preferably 11.0, more preferably 10.0 as measured by
the below-mentioned evaluation method.
The white inorganic particles (3) having a refractive index of not
less than 2.0 have an ultraviolet light-shielding property of
preferably not less than 60%, more preferably not less than 65% as
measured by the below-mentioned evaluation method.
The gluing agent used in the present invention may be of any kind
as long as the black pigment can be coated onto the surface of the
white inorganic particle therethrough. Examples of the preferred
gluing agents may include organosilicon compounds such as
alkoxysilanes, fluoroalkylsilanes and polysiloxanes; various
coupling agents such as silane-based coupling agents,
titanate-based coupling agents, aluminate-based coupling agents and
zirconate-based coupling agents; oligomer compounds, polymer
compounds or the like. These gluing agents may be used alone or in
the form of a mixture of any two or more thereof. In the
consideration of adhesion strength of the black pigment onto the
surface of the white inorganic particle through the gluing agent,
the more preferred gluing agents are the organosilicon compounds
such as alkoxysilanes, fluoroalkylsilanes and polysiloxanes, and
various coupling agents such as silane-based coupling agents,
titanate-based coupling agents, aluminate-based coupling agents and
zirconate-based coupling agents.
More specifically, in the case where the fine silica particles (1)
are used as the core particles, as the gluing agents, there may be
suitably used organosilicon compounds or silane-based coupling
agents. In particular, the use of the organosilane compounds
obtainable from alkoxysilanes represented by the below-mentioned
formula (I) is more preferred.
As organosilicon compounds used in the present invention, at least
one organosilicon compound selected from the group consisting of
(1) organosilane compounds obtained from alkoxysilane compounds;
(2) polysiloxanes, or modified polysiloxanes selected from the
group consisting of (2-A) polysiloxanes modified with at least one
compound selected from the group consisting of polyethers,
polyesters and epoxy compounds (hereinafter referred to merely as
"modified polysiloxanes"), and (2-B) polysiloxanes whose molecular
terminal is modified with at least one group selected from the
group consisting of carboxylic acid groups, alcohol groups and a
hydroxyl group; and (3) fluoroalkyl organosilane compounds obtained
from fluoroalkylsilane compounds.
The organosilane compounds (1) can be produced from alkoxysilane
compounds represented by the formula (I):
wherein R.sup.1 is C.sub.6 H.sub.5 --, (CH.sub.3).sub.2 CHCH.sub.2
-- or n-C.sub.b H.sub.2b+1 -- (wherein b is an integer of 1 to 18);
X is CH.sub.3 O-- or C.sub.2 H.sub.5 O--; and a is an integer of 0
to 3.
Specific examples of the alkoxysilane compounds may include
methyltriethoxysilane, dimethyldiethoxysilane,
phenyltriethyoxysilane, diphenyldiethoxysilane,
dimethyldimethoxysilane, methyltrimethoxysilane,
phenyltrimethoxysilane, diphenyldimethoxysilane,
isobutyltrimethoxysilane, decyltrimethoxysilane or the like. Among
these alkoxysilane compounds, in view of the coating and/or
adhering effect of the black pigments, methyltriethoxysilane,
methyltrimethoxysilane, dimethyldimethoxysilane,
isobutyltrimethoxysilane and phenyltriethyoxysilane are preferred,
and methyltriethoxysilane, methyltrimethoxysilane,
dimethyldimethoxysilane and phenyltriethyoxysilane are more
preferred.
As the polysiloxanes (2), there may be used those compounds
represented by the formula (II):
##STR1##
wherein R.sup.2 is H-- or CH.sub.3 --, and d is an integer of 15 to
450.
Among these polysiloxanes, in view of the coating and/or adhering
effect of the black pigment, polysiloxanes having methyl hydrogen
siloxane units are preferred.
As the modified polysiloxanes (2-A), there may be used: (a1)
polysiloxanes modified with polyethers represented by the formula
(III):
##STR2##
wherein R.sup.3 is --(--CH.sub.2 --).sub.h --; R.sup.4 is
--(--CH.sub.2 --).sub.i --CH.sub.3 ; R.sup.5 is --OH --COOH,
--CH.dbd.CH.sub.2, --CH(CH.sub.3).dbd.CH.sub.2 or --(--CH.sub.2
--).sub.j --CH.sub.3 ; R.sup.6 is --(--CH.sub.2 --).sub.k
--CH.sub.3 ; g and h are an integer of 1 to 15; i, j and k are an
integer of 0 to 15; e is an integer of 1 to 50; and f is an integer
of 1 to 300; (a2) polysiloxanes modified with polyesters
represented by the formula (IV):
##STR3##
wherein R.sup.7, R.sup.8 and R.sup.9 are --(--CH.sub.2 --).sub.q --
and may be the same or different; R.sup.10 is --OH, --COOH,
--CH.dbd.CH.sub.2, --CH(CH.sub.3).dbd.CH.sub.2 or --(--CH.sub.2
--).sub.r --CH.sub.3 ; R.sup.11 is --(--CH.sub.2 --).sub.s
--CH.sub.3 ; n and q are an integer of 1 to 15; r and s are an
integer of 0 to 15; e' is an integer of 1 to 50; and f' is an
integer of 1 to 300; (a3) polysiloxanes modified with epoxy
compounds represented by the formula (V):
##STR4##
wherein R.sup.12 is --(--CH.sub.2 --).sub.v --; v is an integer of
1 to 15; t is an integer of 1 to 50; and u is an integer of 1 to
300; or a mixture thereof.
Among these modified polysiloxanes (2-A), in view of the coating
and/or adhering effect of the black pigment, the polysiloxanes
modified with the polyethers represented by the formula (III), are
preferred.
As the terminal-modified polysiloxanes (2-B), there may be used
those represented by the formula (VI):
##STR5##
wherein R.sup.13 and R.sup.14 are --OH, R.sup.16 OH or R.sup.17
COOH and may be the same or different; R.sup.15 is --CH.sub.3 or
--C.sub.6 H.sub.5 ; R.sup.16 and R.sup.17 are --(--CH.sub.2
--).sub.y --; wherein y is an integer of 1 to 15; w is an integer
of 1 to 200; and x is an integer of 0 to 100.
Among these terminal-modified polysiloxanes, in view of the coating
and/or adhering effect of the black pigment, the polysiloxanes
whose terminals are modified with carboxylic acid groups are
preferred.
The fluoroalkyl organosilane compounds (3) may be produced from
fluoroalkylsilane compounds represented by the formula (VII):
wherein R.sup.18 is CH.sub.3 --, C.sub.2 H.sub.5 --, CH.sub.3 O--
or C.sub.2 H.sub.5 O--; X is CH.sub.3 O-- or C.sub.2 H.sub.5 O--;
and z is an integer of 0 to 15; and a' is an integer of 0 to 3.
Specific examples of the fluoroalkylsilane compounds may include
trifluoropropyl trimethoxysilane, tridecafluorooctyl
trimethoxysilane, heptadecafluorodecyl trimethoxysilane,
heptadecafluorodecylmethyl dimethoxysilane, trifluoropropyl
triethoxysilane, tridecafluorooctyl triethoxysilane,
heptadecafluorodecyl triethoxysilane, or the like. Among these
fluoroalkylsilane compounds, in view of the coating and/or adhering
effect of the black pigment, trifluoropropyl trimethoxysilane,
tridecafluorooctyl trimethoxysilane and heptadecafluorodecyl
trimethoxysilane are preferred, and trifluoropropyl
trimethoxysilane and tridecafluorooctyl trimethoxysilane are more
preferred.
As the silane-based coupling agents, there may be exemplified
vinyltrimethoxysilane, vinyltriethoxysilane,
.gamma.-aminopropyltriethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane,
.gamma.-mercaptopropyltrimethoxysilane,
.gamma.-methacryloxypropyltrimethoxysilane,
N-.beta.(aminoethyl)-.gamma.-aminopropyltrimethoxysilane,
.gamma.-glycidoxypropylmethyldimethoxysilane,
.gamma.-chloropropyltrimethoxysilane or the like.
As the titanate-based coupling agents, there may be exemplified
isopropyltristearoyl titanate,
isopropyltris(dioctylpyrophosphate)titanate,
isopropyltri(N-aminoethyl-aminoethyl)titanate,
tetraoctylbis(ditridecylphosphate)titanate,
tetra(2,2-diaryloxymethyl-1-butyl)bis(ditridecyl)phosphate
titanate, bis(dioctylpyrophosphate)oxyacetate titanate,
bis(dioctylpyrophosphate)ethylene titanate or the like.
As the aluminate-based coupling agents, there may be exemplified
acetoalkoxyaluminum diisopropilate,
aluminumdiisopropoxymonoethylacetoacetate,
aluminumtrisethylacetoacetate, aluminumtrisacetylacetonate or the
like.
As the zirconate-based coupling agents, there may be exemplified
zirconiumtetrakisacetylacetonate,
zirconiumdibutoxybisacetylacetonate,
zirconiumtetrakisethylacetoacetate,
zirconiumtributoxymonoethylacetoacetate,
zirconiumtributoxyacetylacetonate or the like.
It is preferred to use oligomer compounds having a molecular weight
of from 300 to less than 10,000. It is preferred to use polymer
compounds having a molecular weight of about 10,000 to about
100,000. In the consideration of forming a uniform coating layer on
the white inorganic particles, the oligomers or polymer compounds
are preferably in a liquid state, or soluble in water or various
solvents.
The amount of the gluing agent-coating layer is preferably 0.01 to
15.0% by weight, more preferably 0.02 to 12.5% by weight, still
more preferably 0.03 to 10.0% by weight (calculated as C) based on
the weight of the gluing agent-coated white inorganic
particles.
When the amount of the gluing agent-coating layer is less than
0.01% by weight, it may be difficult to coat and/or adhere not less
than one part by weight of the black pigment onto 100 parts by
weight of the white inorganic particles. When the amount of the
gluing agent-coating layer is more than 15.0% by weight, since it
is possible to coat and/or adhere 1 to 500 parts by weight of the
black pigment onto 100 parts by weight of the white inorganic
particles therethrough, it is unnecessary to form the gluing
agent-coating layer in an amount of more than 15.0% by weight.
The black pigments usable in the present invention, include usually
aniline black and carbon black. Especially, as the black pigment
for the tread rubber composition using the silica particles (1),
carbon black is usable in order to reduce the electric resistance.
Examples of the carbon black may include furnace black, channel
black, acetylene black or the like.
In the present invention, in order to impart a clear black color to
the composite particles, the above black pigments may be used in
combination with the other organic pigments. Examples of the other
organic pigments may include organic blue-based pigments comprising
phthalocyanine-based pigments such as metal-free phthalocyanine
blue, phthalocyanine blue and fast sky blue. In case where total
amount of the black pigments and the other organic pigments does
not exceed 500 parts by weight based on 100 parts by weight of the
white inorganic particles as core particles, the amount of the
other organic pigments is preferably not more than 490 parts by
weight based on 100 parts by weight of the white inorganic
particles as core particles.
The total amount of the black pigments coated is usually 1 to 500
parts by weight based on 100 parts by weight of the core
particles.
More specifically, the amount of carbon black coated onto the
silica particles (1) for the tread rubber composition is usually 1
to 500 parts by weight, preferably 30 to 500 parts by weight, more
preferably 50 to 500 parts by weight based on 100 parts by weight
of the silica particles (1).
When the amount of carbon black coated onto the silica particles
(1) is less than 1 part by weight, it may be difficult to obtain
composite particles having a sufficiently low volume resistivity
value and a sufficient blackness because of too small amount of
carbon black coated.
When the amount of carbon black coated onto the silica particles
(1) is more than 500 parts by weight, although it is possible to
obtain a black composite particles having sufficient blackness and
volume resistivity value, the carbon black may tend to be desorbed
from the silica particles because of too large amount of the carbon
black coated. As a result, the obtained composite particles may
tend to be deteriorated in dispersibility in the tread rubber
composition.
The amount of the black pigments coated and/or adhered onto each of
the white inorganic particles (2) having a refractive index of less
than 2.0 and the white inorganic particles (3) having a refractive
index of not less than 2.0, is preferably 1 to 500 parts by weight,
more preferably 2 to 400 parts by weight, still more preferably 5
to 300 parts by weight based on 100 parts by weight of the
respective white inorganic particles.
When the amount of the black pigments coated onto the white
inorganic particles (2) or the white inorganic particles (3) is
less than 1 part by weight or more than 500 parts by weight, it may
be difficult to obtain the aimed composite particles of the present
invention.
The shape and size of the composite particles according to the
present invention may vary depending upon those of the white
inorganic particles as core particles. The composite particles have
a particle configuration similar to that of the core particles.
Namely, the composite particles of the present invention have an
average particle diameter of usually 0.001 to 12.0 .mu.m.
More specifically, in the case where the silica particles (1) are
used as core particles, the average particle diameter of the
obtained composite particles is preferably 0.001 to 0.50 .mu.m,
more preferably 0.002 to 0.45 .mu.m, still more preferably 0.003 to
0.40 .mu.m.
When the average particle diameter of the composite particles
produced by using the silica particles (1) as core particles is
more than 0.50 .mu.m, it may be difficult to uniformly disperse
such composite particles in the tread rubber composition because of
too large particle size thereof. When the average particle diameter
thereof is less than 0.001 .mu.m, the obtained composite particles
tend to be agglomerated together by the increase of intermolecular
force therebetween due to fine particles, so that it may be
difficult to uniformly disperse the composite particles in the
tread rubber composition.
In the case where the white inorganic particles (2) having a
refractive index of less than 2.0 or the white inorganic particles
(3) having a refractive index of not less than 2.0 are used as core
particles, the average particle diameter of the obtained composite
particles is usually 0.001 to 12.0 .mu.m, preferably 0.0015 to 11.0
.mu.m, more preferably 0.002 to 10.0 .mu.m.
When the average particle diameter of the composite particles
produced by using the white inorganic particles (2) or the white
inorganic particles (3) as core particles is more than 12.0 .mu.m,
the obtained composite particles may tend to be deteriorated in
tinting strength because of too large particle size thereof. When
the average particle diameter of the composite particles produced
by using the white inorganic particles (2) or the white inorganic
particles (3) as core particles are less than 0.001 .mu.m, it may
be difficult to uniformly disperse such particles in vehicle.
The composite particles of the present invention have a BET
specific surface area value of usually 0.5 to 500 m.sup.2 /g.
More specifically, the composite particles produced by using the
silica particles (1) as core particles, have a BET specific surface
area value of preferably 20 to 500 m.sup.2 /g, more preferably 25
to 400 m.sup.2 /g, still more preferably 30 to 300 m.sup.2 /g. When
the BET specific surface area value thereof is less than 20 m.sup.2
/g, the obtained composite particles may tend to become coarse, or
sintering may tend to be caused within or between the particles, so
that it may be difficult to uniformly disperse such particles in
the tread rubber composition. When the BET specific surface area
value thereof is more than 500 m.sup.2 /g, the obtained composite
particles tend to be agglomerated together by the increase of
intermolecular force therebetween due to fine particles, so that it
may be difficult to uniformly disperse the composite particles in
the tread rubber composition.
The composite particles produced by using the white inorganic
particles (2) having a refractive index of less than 2.0 or the
white inorganic particles (3) having a refractive index of not less
than 2.0 as core particles according to the present invention, have
a BET specific surface area value of usually 0.5 to 500 m.sup.2 /g,
preferably 1.0 to 400 m.sup.2 /g, more preferably 1.5 to 300
m.sup.2 /g. When the BET specific surface area value thereof is
less than 0.5 m.sup.2 /g, the obtained composite particles may tend
to become coarse, or sintering may tend to be caused within or
between the particles, resulting in poor tinting strength.
The composite particles produced by using carbon black as the black
pigments according to the present invention have a volume
resistivity value of usually less than 1.0.times.10.sup.7
.OMEGA..multidot.cm, and the composite particles produced by using
aniline black as the black pigments according to the present
invention have a volume resistivity value of usually not less than
1.0.times.10.sup.6 .OMEGA..multidot.cm.
More specifically, in the case where carbon black is used as the
black pigments, the composite particles produced by using the
silica particles (1) as core particles, have a volume resistivity
value of preferably less than 1.0.times.10.sup.5
.OMEGA..multidot.cm, more preferably not more than
5.0.times.10.sup.4 .OMEGA..multidot.cm, still more preferably not
more than 1.0.times.10.sup.4 .OMEGA..multidot.cm. When the volume
resistivity value thereof is not less than 1.0.times.10.sup.5
.OMEGA..multidot.cm, it may be difficult to sufficiently reduce the
volume resistivity value of the obtained tread rubber composition.
The lower limit of the volume resistivity value of the composite
particles produced by using the silica particles (1) as core
particles, is preferably 1.0.times.10 .OMEGA..multidot.cm.
In the case where carbon black is used as the black pigments, the
composite particles produced by using the white inorganic particles
(2) having a refractive index of less than 2.0 or the white
inorganic particles (3) having a refractive index of not less than
2.0 as core particles according to the present invention, have a
volume resistivity value of usually less than 1.0.times.10.sup.7
.OMEGA..multidot.cm, preferably not more than 5.0.times.10.sup.6
.OMEGA..multidot.cm, more preferably not more than
1.0.times.10.sup.6 .OMEGA..multidot.cm. In the case where aniline
black is used as the black pigments, the composite particles
produced by using the white inorganic particles (2) or the white
inorganic particles (3) as core particles, have a volume
resistivity value of usually not less than 1.0.times.10.sup.6
.OMEGA..multidot.cm, preferably not less than 5.0.times.10.sup.6
.OMEGA..multidot.cm, more preferably not less than
1.0.times.10.sup.7 .OMEGA..multidot.cm.
As to the blackness of the composite particles produced by using
the silica particles (1) as core particles, the L* value thereof is
preferably not more than 22.0, more preferably not more than 21.0,
most preferably not more than 20.0. When the L* value thereof is
more than 22.0, the obtained composite particles exhibit a too high
brightness and, therefore, may fail to show an excellent blackness.
The lower limit of the L* value is preferably 14.5.
As to the blackness of the composite particles produced by using
the white inorganic particles (2) having a refractive index of less
than 2.0 as core particles, the L* value thereof is preferably not
more than 30.0, more preferably not more than 29.0, still more
preferably not more than 28.0. When the L* value thereof is more
than 30.0, the obtained composite particles exhibit a too high
brightness and, therefore, may fail to show an excellent blackness.
The lower limit of the L* value is preferably 14.5.
As to the hue of the composite particles produced by using the
white inorganic particles (3) having a refractive index of not less
than 2.0 as core particles, the L* value thereof is usually not
more than 90.0, preferably not more than 80.0, more preferably not
more than 70.0. The lower limit of the L* value is preferably
14.5.
As to the light resistance of the composite particles according to
the present invention, the .DELTA.E* value thereof is preferably
not more than 5.0, more preferably not more than 4.0 as measured by
the below-mentioned evaluation method.
The desorption percentage of the black pigments from the composite
particles of the present invention is preferably not more than 20%,
more preferably not more than 15%. When the desorption percentage
of the black pigments from the composite particles is more than
20%, the composite particles may tend to be inhibited from being
uniformly dispersed in the vehicle or tread rubber composition, by
the existence of the desorbed black pigments.
The composite particles produced by using the white inorganic
particles (2) having a refractive index of less than 2.0 or the
white inorganic particles (3) having a refractive index of not less
than 2.0 as core particles according to the present invention, have
a tinting strength of preferably not less than 110%, more
preferably not less than 115%, still more preferably not less than
120% as measured by the below-mentioned evaluation method.
The composite particles produced by using the white inorganic
particles (2) having a refractive index of less than 2.0 or the
white inorganic particles (3) having a refractive index of not less
than 2.0 as core particles according to the present invention, have
a repose angle of preferably not more than 45.degree., more
preferably not more than 40.degree..
The composite particles produced by using the white inorganic
particles (2) having a refractive index of less than 2.0 or the
white inorganic particles (3) having a refractive index of not less
than 2.0 as core particles according to the present invention, have
a surface activity of preferably not more than 2%, more preferably
not more than 1.5% as measured by the below-mentioned evaluation
method.
The composite particles produced by using the white inorganic
particles (3) having a refractive index of not less than 2.0 as
core particles according to the present invention, have an
ultraviolet light-shielding property of preferably not less than
80%, more preferably not less than 85% as measured by the
below-mentioned evaluation method.
In the composite particles according to the present invention, if
required, the surface of the white inorganic particle may be
previously coated with at least one compound selected from the
group consisting of hydroxides of aluminum, oxides of aluminum,
hydroxides of silicon and oxides of silicon (hereinafter referred
to as "hydroxides and/or oxides of aluminum and/or silicon"). The
composite particles produced by using the white inorganic particles
having the hydroxides and/or oxides of aluminum and/or silicon coat
as core particles, can be more effectively prevented from
undergoing desorption of black pigment from the surface of the
white inorganic particle, and can exhibit a higher light
resistance, as compared to composite particles produced by using
the white inorganic particles having no hydroxides and/or oxides of
aluminum and/or silicon coat.
The amount of the hydroxides and/or oxides of aluminum and/or
silicon coat is 0.01 to 20% by weight (calculated as Al, SiO.sub.2
or sum of Al and SiO.sub.2) based on the weight of the white
inorganic particles coated with the hydroxides and/or oxides of
aluminum and/or silicon.
When the amount of the hydroxides and/or oxides of aluminum and/or
silicon coat is less than 0.01% by weight, it may be difficult to
attain the improved effect of reducing the desorption percentage of
black pigment and the improved effect of enhancing the light
resistance. As long as the amount of the hydroxides and/or oxides
of aluminum and/or silicon coat is in the range of 0.01 to 20% by
weight, the improved effect of reducing the desorption percentage
of black pigment and the improved effect of enhancing the light
resistance can be sufficiently attained. Therefore, it is
unnecessary to form the hydroxides and/or oxides of aluminum and/or
silicon coat in an amount of more than 20% by weight.
The composite particles produced by using as core particles, the
white inorganic particles coated with hydroxides and/or oxides of
aluminum and/or silicon according to the present invention, are
substantially the same in particle size, BET specific surface area
value, blackness, tinting strength and volume resistivity value as
those of the composite particles produced by using the white
inorganic particles having no hydroxides and/or oxides of aluminum
and/or silicon coat according to the present invention. The
desorption percentage of the black pigments from the composite
particles as well as the light resistance thereof can be improved
by forming the hydroxides and/or oxides of aluminum and/or silicon
coat on the white inorganic particles. Specifically, by forming
such an hydroxides and/or oxides of aluminum and/or silicon coat on
the white inorganic particles as core particles, the properties of
the obtained composite particles can be improved such that the
desorption percentage of the black pigments therefrom is preferably
not more than 15%, more preferably not more than 10%, and as to the
light resistance, the .DELTA.E* value thereof is usually not more
than 4.0, preferably not more than 3.0.
When the silica particles (1) are used as the core particles, the
surface of the obtained composite particles may be further coated,
if required, with a fatty acid, a metal salt of fatty acid or a
silane-based coupling agent. The composite particles coated with
the fatty acid, the metal salt of fatty acid or the silane-based
coupling agent are enhanced in dispersibility in the tread rubber
composition as compared to uncoated composite particles.
Examples of the fatty acid used in the present invention may
include saturated or unsaturated fatty acids. Among these fatty
acids, those having 12 to 22 carbon atoms are preferred.
Examples of the metal salt of fatty acid used in the present
invention may include metal salts of saturated or unsaturated fatty
acids, more preferably metal salts of a fatty acid having 12 to 18
carbon atoms, and a metal selected from the group consisting of
alkali earth metals such as magnesium, calcium, strontium and
barium, alkali metals such as lithium, sodium and potassium, zinc,
aluminum, copper, iron, lead and tin. In the consideration of good
dispersibility in the tread rubber composition, alkali earth metal
salts of stearic acid and zinc stearate are preferred.
The silane-based coupling agent used in the present invention may
be selected from those ordinarily blended in rubbers. Specific
examples of the silane-based coupling agent may include vinyl
trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane,
vinyl tris(.beta.-methoxyethoxy)silane,
.beta.-(3,4-epoxycyclohexy)ethyl trimethoxysilane,
.gamma.-glycidoxypropyl trimethoxysilane,
.gamma.-glycidoxypropylmethyl dimethoxysilane,
.gamma.-methacryloxypropyl trimethoxysilane,
N-.beta.-(aminoethyl)-.gamma.-aminopropylmethyl dimethoxysilane,
N-.beta.-(aminoethyl)-.gamma.-aminopropyl trimethoxysilane,
N-phenyl-.gamma.-aminopropyl trimethoxysilane, .gamma.-aminopropyl
trimethoxysilane, .gamma.-aminopropyl triethoxysilane,
.gamma.-chloropropyl trimethoxysilane, .gamma.-mercaptopropyl
trimethoxysilane, bis(3-(trimethoxysilyl)propyl)tetrasulfene,
.gamma.-trimethoxysilylpropyl dimethylthiocarbamyl tetrasulfene,
.gamma.-trimethoxysilylpropyl benzothiazyl tetrasulfene or the
like.
In the consideration of good reinforcing effect in the tread rubber
composition, as the silane-based coupling agent, there may be used
those having a functional group capable of reacting with a
carbon-carbon double bond of the rubber such as polysulfide group,
mercapto group and epoxy group.
Specific examples of the silane-based coupling agents having a
polysulfide group may include bis(3-(trimethoxysilyl)propyl)
tetrasulfene, .gamma.-trimethoxysilylpropyl dimethylthiocarbamyl
tetrasulfene, .gamma.-trimethoxysilylpropyl benzothiazyl
tetrasulfene or the like. Specific examples of the silane-based
coupling agents having a mercapto group may include
.gamma.-mercaptopropyl trimethoxysilane or the like. Specific
examples of the silane-based coupling agents having an epoxy group
may include .beta.-(3,4-epoxycyclohexy)ethyl trimethoxysilane,
.gamma.-glycidoxypropyl trimethoxysilane or the like.
The coating amount of the fatty acid, metal salt of fatty acid or
silane-based coupling agent is preferably 0.1 to 10.0% by weight,
more preferably 0.2 to 7.5% by weight, still more preferably 0.3 to
5.0% by weight (calculated as C) based on the weight of the
composite particles coated with the fatty acid, metal salt of fatty
acid or silane-based coupling agent.
When the coating amount of the fatty acid, metal salt of fatty acid
or silane-based coupling agent is less than 0.1% by weight, it may
be difficult to improve the dispersibility of the composite
particles in the tread rubber composition. When the coating amount
of the fatty acid, metal salt of fatty acid or silane-based
coupling agent is more than 10.0% by weight, the effect of
improving the dispersibility in the tread rubber composition is
already saturated and, therefore, the coating with such a large
amount of the fatty acid, metal salt of fatty acid or silane-based
coupling agent is unnecessary and meaningless.
The composite particles coated with the fatty acid, metal salt of
fatty acid or silane-based coupling agent which are produced by
using the silica particles (1) as core particles, are substantially
the same in particle size, BET specific surface area value, volume
resistivity value, blackness, light resistance and carbon black
desorption percentage as those of the uncoated composite particles
produced by using the silica particles (1) as core particles
according to the present invention.
Next, the tread rubber composition containing the composite
particles produced by using the silica particles (1) as core
particles according to the present invention, is described.
The tread rubber composition containing as a filler the black
composite particles produced by using the silica particles (1) as
core particles according to the present invention, exhibits a
dispersion condition of Rank 4 or 5, preferably Rank 5; a wear
resistance of preferably not less than 103, more preferably not
less than 105 (as relative value); a volume resistivity value of
preferably not more than 1.0.times.10.sup.5 .OMEGA..multidot.cm,
more preferably not more than 5.0.times.10.sup.4
.OMEGA..multidot.cm; a tensile strength of preferably not less than
23.0 MPa, more preferably not less than 23.5 MPa; and a light
resistance (.DELTA.E* value) of preferably not more than 5.0, more
preferably not more than 4.5, still more preferably not more than
4.0.
The tread rubber composition containing as a filler the black
composite particles produced by using the silica particles (1) as
core particles, which black composite particles is coated with the
fatty acid, metal salt of fatty acid or silane-based coupling agent
according to the present invention, exhibits a dispersion condition
of preferably Rank 5; a wear resistance of preferably not less than
105, more preferably not less than 107 (as relative value); a
volume resistivity value of preferably not more than
1.0.times.10.sup.5 .OMEGA..multidot.cm, more preferably not more
than 5.0.times.10.sup.4 .OMEGA..multidot.cm; a tensile strength of
preferably not less than 23.5 MPa, more preferably not less than
24.0 MPa; and a light resistance (.DELTA.E* value) of preferably
not more than 4.5, more preferably not more than 4.0, still more
preferably not more than 3.5.
The tread rubber composition containing as a filler the black
composite particles produced by using the silica particles (1) as
core particles, which silica particles coated with at least one
compound selected from the group consisting of hydroxides of
aluminum, oxides of aluminum, hydroxides of silicon and oxides of
silicon, according to the present invention, exhibits a dispersion
condition of preferably Rank 5; a wear resistance of preferably not
less than 105, more preferably not less than 107 (as relative
value); a volume resistivity value of preferably not more than
1.0.times.10.sup.5 .OMEGA..multidot.cm, more preferably not more
than 5.0.times.10.sup.4 .OMEGA..multidot.cm; a tensile strength of
preferably not less than 23.5 MPa, more preferably not less than
24.0 MPa; and a light resistance (.DELTA.E* value) of preferably
not more than 4.5, more preferably not more than 4.0, still more
preferably not more than 3.5.
In the tread rubber composition of the present invention, the black
composite particles may be blended in an amount of usually 10 to
200 parts by weight based on 100 parts by weight of the rubber
component contained in the composition. In the consideration of
good handling property of the tread rubber composition, the amount
of the black composite particles blended is preferably 15 to 150
parts by weight, more preferably 20 to 100 parts by weight based on
100 parts by weight of the rubber component.
In addition to the composite particles and known rubber components,
the tread rubber composition of the present invention may further
contain, if required, various additives ordinarily used in tread
rubber compositions such as curing agent, curing promoter, coupling
agent, filler, plasticizer, anti-aging agent and the like.
As the rubber component, there may be used natural rubber (NR),
polyisoprene rubber (IR), styrene-butadiene copolymer rubber (SBR),
polybutadiene rubber (BR), butyl rubber (IIR), halogenated butyl
rubber (X-IIR), acrylonitrile-butadiene rubber (NBR), chloroprene
rubber, ethylene-propylene copolymer rubber,
ethylene-propylene-diene copolymer rubber, styrene-isoprene
copolymer rubber, styrene-isoprene-butadiene copolymer rubber,
isoprene-butadiene copolymer rubber, chloro-sulfonated
polyethylene, acrylic rubber, epichlorohydrin rubber, polysulfide
rubber, silicone rubber, fluorine-contained rubber, urethane
rubber, or mixtures thereof. The rubber component of the tread
rubber composition preferably contains as a main component, a
diene-based rubber such as natural rubber (NR), polyisoprene rubber
(IR), styrene-butadiene copolymer rubber (SBR), polybutadiene
rubber (BR), butyl rubber (IIR), halogenated butyl rubber (X-IIR)
and acrylonitrile-butadiene rubber (NBR).
The tread rubber composition of the present invention can be
produced by kneading the above rubber component and the black
composite particles, if required, together with various additives,
by a known method using a Banbury mixer, a mixing roll or the like,
and then vulcanizing the resultant kneaded material at a
temperature of usually 120 to 180.degree. C.
Next, the paint containing the composite particles using the white
inorganic particles (2) having a refractive index of less than 2.0
or the white inorganic particles (3) having a refractive index of
not less than 2.0 according to the present invention is
described.
The solvent-based paint containing the black composite particles
produced by using the white inorganic particles (2) having a
refractive index of less than 2.0 as core particles according to
the present invention, exhibits a storage stability (.DELTA.E*
value) of preferably not more than 1.5, more preferably not more
than 1.2. As to the blackness of a coating film formed from the
solvent-based paint, the L* value thereof is preferably not more
than 30.0, more preferably not more than 29.0, still more
preferably not more than 28.0, and the lower limit of the L* value
is preferably 14.5. The coating film formed from the solvent-based
paint further has a gloss of preferably 75 to 110%, more preferably
80 to 110%; and a light resistance (.DELTA.E* value) of preferably
not more than 5.0, more preferably not more than 4.0.
The solvent-based paint containing the black composite particles
produced by using as core particles, the white inorganic particles
(2) having a refractive index of less than 2.0, which are coated
with at least one compound selected from the group consisting of
hydroxides of aluminum, oxides of aluminum, hydroxides of silicon
and oxides of silicon, exhibits a storage stability (.DELTA.E*
value) of preferably not more than 1.5, more preferably not more
than 1.2. As to the blackness of a coating film formed from the
solvent-based paint, the L* value thereof is preferably not more
than 30.0, more preferably not more than 29.0, still more
preferably not more than 28.0, and the lower limit of the L* value
is preferably 14.5. The coating film formed from the solvent-based
paint further has a gloss of preferably 80 to 115%, more preferably
85 to 115%; and a light resistance (.DELTA.E* value) of preferably
not more than 4.0, more preferably not more than 3.0.
The water-based paint containing the black composite particles
produced by using the white inorganic particles (2) having a
refractive index of less than 2.0 as core particles, exhibits a
storage stability (.DELTA.E* value) of preferably not more than
1.5, more preferably not more than 1.2. As to the blackness of a
coating film formed from the water-based paint, the L* value
thereof is preferably not more than 30.0, more preferably not more
than 29.0, still more preferably not more than 28.0, and the lower
limit of the L* value is preferably 14.5. The coating film formed
from the water-based paint further has a gloss of preferably 70 to
110%, more preferably 75 to 110%; and a light resistance (.DELTA.E*
value) of preferably not more than 5.0, more preferably not more
than 4.0.
The water-based paint containing the black composite particles
produced by using as core particles, the white inorganic particles
(2) having a refractive index of less than 2.0, which are coated
with at least one compound selected from the group consisting of
hydroxides of aluminum, oxides of aluminum, hydroxides of silicon
and oxides of silicon, exhibits a storage stability (.DELTA.E*
value) of preferably not more than 1.5, more preferably not more
than 1.2. As to the blackness of a coating film formed from the
water-based paint, the L* value thereof is preferably not more than
30.0, more preferably not more than 29.0, still more preferably not
more than 28.0, and the lower limit of the L* value is preferably
14.5. The coating film formed from the water-based paint further
has a gloss of preferably 75 to 115%, more preferably 80 to 115%;
and a light resistance (.DELTA.E* value) of preferably not more
than 4.0, more preferably not more than 3.0.
The solvent-based paint containing the composite particles produced
by using the white inorganic particles (3) having a refractive
index of not less than 2.0 as core particles, exhibits a storage
stability (.DELTA.E* value) of preferably not more than 1.5. more
preferably not more than 1.2. The coating film formed from the
above solvent-based paint has a gloss of preferably 75 to 110%,
more preferably 80 to 110%; a light resistance (.DELTA.E* value) of
preferably not more than 5.0, more preferably not more than 4.0. As
to the hue of the coating film-formed from the above solvent-based
paint, the L* value thereof is preferably not more than 90.0, more
preferably not more than 80.0, still more preferably not more than
70.0, and the lower limit of the L* value is preferably 14.5.
The solvent-based paint containing the composite particles produced
by using as core particles, the white inorganic particles (3)
having a refractive index of not less than 2.0, which are coated
with at least one compound selected from the group consisting of
hydroxides of aluminum, oxides of aluminum, hydroxides of silicon
and oxides of silicon, exhibits a storage stability (.DELTA.E*
value) of preferably not more than 1.5, more preferably not more
than 1.2. The coating film formed from the above solvent-based
paint has a gloss of preferably 80 to 115%, more preferably 85 to
115%; a light resistance (.DELTA.E* value) of preferably not more
than 4.0, more preferably not more than 3.0. As to the hue of the
coating film formed from the above solvent-based paint, the L*
value thereof is preferably not more than 90.0, more preferably not
more than 80.0, still more preferably not more than 70.0, and the
lower limit of the L* value is preferably 14.5.
The water-based paint containing the composite particles produced
by using the white inorganic particles (3) having a refractive
index of not less than 2.0 as core particles, exhibits a storage
stability (.DELTA.E* value) of preferably not more than 1.5, more
preferably not more than 1.2. The coating film formed from the
above water-based paint has a gloss of preferably 70 to 110%, more
preferably 75 to 110%; a light resistance (.DELTA.E* value) of
preferably not more than 5.0, more preferably not more than 4.0. As
to the hue of the coating film formed from the above water-based
paint, the L* value thereof is preferably not more than 90.0, more
preferably not more than 80.0, still more preferably not more than
70.0, and the lower limit of the L* value is preferably 14.5.
The water-based paint containing the composite particles produced
by using as core particles, the white inorganic particles (3)
having a refractive index of not less than 2.0, which are coated
with at least one compound selected from the group consisting of
hydroxides of aluminum, oxides of aluminum, hydroxides of silicon
and oxides of silicon, exhibits a storage stability (.DELTA.E*
value) of preferably not more than 1.5, more preferably not more
than 1.2. The coating film formed from the above water-based paint
has a gloss of preferably 75 to 115%, more preferably 80 to 115%; a
light resistance (.DELTA.E* value) of preferably not more than 4.0,
more preferably not more than 3.0. As to the hue of the coating
film formed from the above water-based paint, the L* value thereof
is preferably not more than 90.0, more preferably not more than
80.0, still more preferably not more than 70.0, and the lower limit
of the L* value is preferably 14.5.
The amount of the composite particles blended in the paint
according to the present invention is in the range of usually 0.5
to 100 parts by weight based on 100 parts by weight of a paint base
material. In the consideration of handling of the paint, the amount
of the composite particles blended in the paint is preferably 1.0
to 100 parts by weight based on 100 parts by weight of the paint
base material.
The paint base material comprises a resin and a solvent, and may
further contain, if required, oil and fats, a defoamer, an extender
pigment, a drying agent, a surfactant, a hardening accelerator, an
assistant, or the like.
Examples of the resin used in the paint base material may include
resins ordinarily used for solvent-based paints or oil-based
printing inks such as acrylic resins, alkyd resins, polyester
resins, polyurethane resins, epoxy resins, phenol resins, melamine
resins, amino resins, vinyl chloride resins, silicone resins,
rosin-based resins such as gum rosin and lime rosin, maleic acid
resins, polyamide resins, nitrocellulose, ethylene-vinyl acetate
copolymer resins, rosin-modified resins such as rosin-modified
phenol resins and rosin-modified maleic acid resins, petroleum
resins or the like. Examples of the resins used in the paint base
material for water-based paints may include resins ordinarily used
for water-based paints or water-based inks such as water-soluble
acrylic resins, water-soluble styrene-maleic acid resins,
water-soluble alkyd resins, water-soluble melamine resins,
water-soluble urethane emulsion resins, water-soluble epoxy resins,
water-soluble polyester resins or the like.
As the solvent for solvent-based paints, there may be exemplified
those solvents ordinarily used for solvent-based paints such as
soybean oil, toluene, xylene, thinner, butyl acetate, methyl
acetate, methyl isobutyl ketone, glycol ether-based solvents such
as methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl
cellosolve and propylene glycol monomethyl ether, ester-based
solvents such as ethyl acetate, butyl acetate and amyl acetate,
aliphatic hydrocarbon-based solvents such as hexane, heptane and
octane, alicyclic hydrocarbon-based solvents such as cyclohexane,
petroleum-based solvents such as mineral spirits, ketone-based
solvents such as acetone and methyl ethyl ketone, alcohol-based
solvents such as methyl alcohol, ethyl alcohol, propyl alcohol and
butyl alcohol, aliphatic hydrocarbons or the like.
As the solvents for water-based paints, there may be used a mixture
of water and a water-soluble organic solvent ordinarily used for
water-based paints such as alcohol-based solvents such as ethyl
alcohol, propyl alcohol and butyl alcohol, glycol ether-based
solvents such as methyl cellosolve, ethyl cellosolve, propyl
cellosolve and butyl cellosolve, oxyethylene or oxypropylene
addition polymers such as diethylene glycol, triethylene glycol,
polyethylene glycol, dipropylene glycol, tripropylene glycol and
polypropylene glycol, alkylene glycols such as ethylene glycol,
propylene glycol and 1,2,6-hexanetriol, glycerin, 2-pyrolidone or
the like
As the fats and oils, there may be used boiled oils obtained by
processing drying oils such as linseed oil, tung oil, oiticica oil
and safflower oil.
As the defoamer, there may be used commercially available products
such as "NOPCO 8034 (tradename)", "SN DEFOAMER 477 (tradename)",
"SN DEFOAMER 5013 (tradename)", "SN DEFOAMER 247 (tradename)" and
"SN DEFOAMER 382 (tradename)" (all produced by SUN NOPCO CO.,
LTD.), "ANTI-FOAM 08 (tradename)" and "EMARGEN 903 (tradename)"
(both produced by KAO CO., LTD.), or the like.
Next, the resin composition containing the composite particles
according to the present invention is described.
The resin composition containing the black composite particles
produced by using the white inorganic particles (2) having a
refractive index of less than 2.0 as core particles according to
the present invention, exhibits a blackness (L* value) of
preferably not more than 30.0, more preferably not more than 29.0,
still more preferably not more than 28.0 provided that the lower
limit of the L* value is preferably 14.5; a dispersing condition of
Rank 4 or 5, preferably Rank 5 as evaluated by the below-mentioned
method; a light resistance (.DELTA.E* value) of preferably not more
than 5.0, more preferably not more than 4.0; and an anti-aging
property (percentage of discolored portion after heating at
190.degree. C. for 120 minutes) of preferably mot more than 15%,
more preferably not more than 10%, still more preferably not more
than 5%.
The resin composition containing the black composite particles
produced by using as core particles the white inorganic particles
(2) having a refractive index of less than 2.0, which are coated
with at least one compound selected from the group consisting of
hydroxides of aluminum, oxides of aluminum, hydroxides of silicon
and oxides of silicon according to the present invention, exhibits
a blackness (L* value) of preferably not more than 30.0, more
preferably not more than 29.0, still more preferably not more than
28.0 provided that the lower limit of the L* value is preferably
14.5; a dispersing condition of Rank 4 or 5, preferably Rank 5 as
evaluated by the below-mentioned method; a light resistance
(.DELTA.E* value) of preferably not more than 4.0, more preferably
not more than 3.0; and an anti-aging property (percentage of
discolored portion after heating at 190.degree. C. for 120 minutes)
of preferably mot more than 15%, more preferably not more than 10%,
still more preferably not more than 5%.
The resin composition containing the composite particles produced
by using the white inorganic particles (3) having a refractive
index of not less than 2.0 as core particles according to the
present invention, exhibits a dispersing condition of preferably
Rank 4 or 5, more preferably Rank 5 as evaluated by the
below-mentioned method; a light resistance (.DELTA.E* value) of
preferably not more than 5.0, more preferably not more than 4.0;
and an anti-aging property (percentage of discolored portion after
heating at 190.degree. C. for 120 minutes) of preferably mot more
than 15%, more preferably not more than 10%, still more preferably
not more than 5%. As to the hue of the above resin composition, the
L* value thereof is preferably not more than 90.0, more preferably
not more than 80.0, still more preferably not more than 70.0, and
the lower limit of the L* value is preferably 14.5.
The resin composition containing the composite particles produced
by using as core particles the white inorganic particles (3) having
a refractive index of not less than 2.0, which are coated with at
least one compound selected from the group consisting of hydroxides
of aluminum, oxides of aluminum, hydroxides of silicon and oxides
of silicon according to the present invention, a dispersing
condition of Rank 4 or 5, preferably Rank 5 as evaluated by the
below-mentioned method; a light resistance (.DELTA.E* value) of
preferably not more than 4.0, more preferably not more than 3.0;
and an anti-aging property (percentage of discolored portion after
heating at 190.degree. C. for 120 minutes) of preferably mot more
than 15%, more preferably not more than 10%, still more preferably
not more than 5%; exhibits a blackness (L* value) of preferably not
more than 90.0, more preferably not more than 80.0, still more
preferably not more than 70.0 provided that the lower limit of the
L* value is preferably 14.5.
The amount of the composite particles blended in the resin
composition according to the present invention is usually in the
range of 0.01 to 200 parts by weight based on 100 parts by weight
of resins contained in the composition. In the consideration of
handling of the resin composition, the amount of the composite
particles blended therein is preferably 0.05 to 150 parts by
weight, more preferably 0.1 to 100 parts by weight based on 100
parts by weight of the resins.
The base material of the resin composition according to the present
invention comprises the composite particles and known thermoplastic
resins, and may further contain, if required, additives such as
lubricants, plasticizers, antioxidants, ultraviolet light
absorbers, various stabilizers or the like.
As the reins, there may be used polyolefins such as polyethylene,
polypropylene, polybutene and polyisobutylene; thermoplastic resins
such as polyvinyl chloride, polymethyl pentene, polyethylene
terephthalate, polybutylene terephthalate, polystyrene,
styrene-acrylic ester copolymers, styrene-vinyl acetate copolymers,
acrylonitrile-butadiene-styrene copolymers,
acrylonitrile-EPDM-styrene copolymers, acrylic resins, polyamides,
polycarbonates, polyacetals and polyurethanes; rosin-modified
maleic acid resins; phenol resins; epoxy resins; polyester resins;
silicone resins; rosin-esters; rosins; natural rubbers, synthetic
rubbers; or the like.
The additives may be added in an amount of usually not more than
50% by weight based on the total amount of the composite particles
and the resin. When the amount of the additives added is more than
50% by weight, the obtained resin composition may be deteriorated
in moldability.
The resin composition is produced by previously intimately mixing
the raw resin material with the composite particles, and then
kneading the resultant mixture using a kneader or an extruder under
heating while applying a strong shear force thereto in order to
deaggregate the agglomerated composite particles and uniformly
disperse the composite particles in the resin. Then, the obtained
resin composition is molded into an aimed shape upon use.
The resin composition containing the composite particles produced
by using as core particles the white inorganic particles (2) having
a refractive index of less than 2.0 or the white inorganic
particles (3) having a refractive index of not less than 2.0, may
also be produced via master batch pellets.
The master batch pellets used in the present invention are produced
(i) by mixing a binder resin as a base material for the paint or
the resin composition with the composite particles, if necessary,
using a mixing device such as ribbon blender, Nauter mixer,
Henschel mixer and Super mixer, kneading and molding the resultant
mixture using a known single-screw kneading extruder or twin-screw
kneading extruder, and then cutting the molded product into
pellets; or (ii) by mixing a binder resin as a base material for
the paint or the resin composition with the composite particles, if
necessary, using a mixing device such as ribbon blender, Nauter
mixer, Henschel mixer and Super mixer, kneading the above mixture
using Banbury mixer, press kneader or the like, and then
pulverizing, molding or cutting the kneaded material into
pellets.
The binder resin and the composite particles may be respectively
supplied in separate batches into the kneader at predetermined
constant ratios, or may be simultaneously supplied thereto in the
form of a mixture of both the components.
The master batch pellets used in the present invention have an
average major diameter of usually 1 to 6 mm, preferably 2 to 5 mm,
and an average minor diameter of usually 2 to 5 mm, preferably 2.5
to 4 mm. When the average major diameter of the master batch
pellets is less than 1 mm, the workability upon production of the
pellets may be deteriorated. When the average major diameter of the
master batch pellets is more than 6 mm, the master batch pellets
are considerably different in size from that of diluting binder
resin particles, so that it may be difficult to sufficiently
disperse the pellets in the diluting binder resin. The master batch
pellets may have any suitable shape such as an amorphous shape, a
granular shape such as spherical shape, a cylindrical shape, a
flake-like shape or the like.
As the binder resin for the master batch pellets of the present
invention, there may be used resins of the same type as the above
binder resin for the paint or the resin composition.
Meanwhile, the composition of the binder resin contained in the
master batch pellets is preferably the same as that of the diluting
binder resin. Also, the binder resin may be different from the
diluting binder resin. In such a case, it is required that kinds of
resins used are determined in view of various properties thereof so
as to attain a good compatibility therebetween.
The amount of the composite particles blended in the master batch
pellets is usually 1 to 200 parts by weight, preferably 1 to 150
parts by weight, more preferably 1 to 100 parts by weight based on
100 parts by weight of the binder resin. When the amount of the
composite particles blended is less than 1 part by weight, the
obtained master batch pellets may be insufficient in melt viscosity
upon kneading, so that it may become difficult to sufficiently mix
and disperse the composite particles in the resin. When the amount
of the composite particles blended is more than 200 parts by
weight, the amount of the binder resin may become comparatively
small, so that it may also become difficult to sufficiently mix and
disperse the composite particles in the resin. In addition, since
even a slight change in amount of the master batch pellets added
causes a considerable change in content of the composite particles
in the resin composition, it may be difficult to control the
content of the composite particles in the resin composition to the
aimed level. Further, mechanical abrasion of products produced from
such master batch pellets becomes remarkable.
Next, the process for producing the composite particles according
to the present invention is described.
The composite particles of the present invention can be produced by
first mixing the white inorganic particles with the gluing agent to
coat the surface of the white inorganic particle with the gluing
agent, and then mixing the thus-obtained gluing agent-coated white
inorganic particles with the black pigment.
The formation of the gluing agent-coating layer on the surface of
the white inorganic particle may be conducted by mechanically
mixing and stirring the particles with a gluing agent solution or
the gluing agent, or by mechanically mixing and stirring the white
inorganic particles while spraying the gluing agent solution or the
gluing agent thereonto. Substantially whole amount of the gluing
agent added is coated on the surface of the white inorganic
particle.
Meanwhile, in the case where alkoxysilanes or fluoroalkylsilanes
are used as the gluing agent, a part of the alkoxysilanes or
fluoroalkylsilanes may be coated in the form of organosilane
compounds produced from the alkoxysilanes or fluoroalkyl
organosilane compounds produced from fluoroalkylsilanes through the
coating step. Even in such a case, subsequent coat of the black
pigment on the gluing agent-coating layer is not adversely
affected.
In order to uniformly coat the gluing agent over the surface of the
white inorganic particle, it is preferred that the agglomerated
white inorganic particles are previously deaggregated using a
crusher.
The mixing and stirring of the white inorganic particles with the
gluing agent and the mixing and stirring of the black pigment with
the gluing agent-coated white inorganic particles, is preferably
carried out using an apparatus capable of applying a shear force to
the powder mixture, especially such an apparatus capable of
simultaneously effecting shear action, spatula stroking and
compression. Examples of such apparatuses may include wheel-type
kneaders, ball-type kneaders, blade-type kneaders, roll-type
kneaders or the like. Among these apparatuses, the wheel-type
kneaders are preferred to effectively practice the present
invention.
Specific examples of the wheel-type kneaders may include edge
runners (similar in meaning to mix muller, Simpson mill and sand
mill), multimill, Stotz mill, Wet pan mill, corner mill, ring
muller or the like. Among these kneaders, preferred are edge
runners, multimill, Stotz mill, Wet pan mill and ring muller, and
more preferred are edge runners. Specific examples of the ball-type
kneaders may include vibration mill or the like. Specific examples
of the blade-type kneaders may include Henschel mixer, planetary
mixer, Nauter mixer or the like. Specific examples of the roll-type
kneaders may include extruders or the like.
The conditions of the mixing and stirring treatment may be selected
so as to uniformly coat the surface of the white inorganic particle
with the gluing agent. Specifically, the mixing and stirring
conditions may be appropriately controlled such that the linear
load is usually 19.6 to 1,960 N/cm (2 to 200 Kg/cm), preferably 98
to 1,470 N/cm (10 to 150 Kg/cm), more preferably 147 to 980 N/cm
(15 to 100 Kg/cm); the treating time is usually 5 minutes to 24
hours, preferably 10 minutes to 20 hours; and the stirring speed is
usually 2 to 2,000 rpm, preferably 5 to 1,000 rpm, more preferably
10 to 800 rpm.
The amount of the gluing agent added is usually 0.15 to 45 parts by
weight based on 100 parts by weight of the white inorganic
particles. When the gluing agent is added in an amount of 0.15 to
45 parts by weight, it is possible to coat a sufficient amount of
black pigments onto the white inorganic particles. Therefore, it is
unnecessary and meaningless to add black pigments in an amount of
more than 45 parts by weight.
After the surface of the white inorganic particle is coated with
the gluing agent, the black pigment is added, and then mixed and
stirred with the gluing agent-coated white inorganic particles to
coat the black pigment onto the gluing agent-coating layer. The
obtained particles may be further subjected to drying or heating
treatments, if required.
It is preferred that the black pigments are gradually added little
by little for a period of preferably about 5 minutes to about 24
hours, more preferably about 5 minutes to about 20 hours, or are
intermittently added in parts until the total amount thereof
reaches 5 to 25 parts by weight based on 100 parts by weight of the
white inorganic particles.
The mixing and stirring conditions may be appropriately selected so
as to form a uniform black pigment coat on the gluing agent-coating
layer, and may be controlled such that the linear load is usually
19.6 to 1,960 N/cm (2 to 200 Kg/cm), preferably 98 to 1,470 N/cm
(10 to 150 Kg/cm), more preferably 147 to 980 N/cm (15 to 100
Kg/cm); the treating time is usually 5 minutes to 24 hours,
preferably 10 minutes to 20 hours; and the stirring speed is
usually 2 to 2,000 rpm, preferably 5 to 1,000 rpm, more preferably
10 to 800 rpm.
As the carbon black particles which are used for producing the
black composite particles for the tread rubber composition, using
the silica particles (1) as core particles, there may be
exemplified commercially available furnace black and channel black,
or the like. Specific examples of the carbon black particles may
include #3050, #3150, #3250, #3750, #3950, MA100, MA7, #1000,
#2400B, #30, MA77, MA8, #650, MA11, #50, #52, #45, #2200B and MA600
(tradenames; produced by Mitsubishi Kagaku Co., Ltd.), SEAST 9H,
SEAST 7H, SEAST 6, SEAST 3H, SEAST 300 and SEAST FM (tradenames;
produced by Tokai Carbon Co., Ltd.), RAVEN 1250, RAVEN 860, RAVEN
1000 and RAVEN 1190ULTRA (tradenames; produced by Colombian
Chemicals Co.), KETCHEN BLACK EC and KETCHEN BLACK EC600JD
(tradenames; produced by Ketchen Black International Co., Ltd.),
BLACK PEARLS-L, BLACK PEARLS 1000, BLACK PERLS 4630, VULCAN XC72,
REGAL 660 and REGAL 400 (tradenames; produced by Cabot Specialty
Chemicals Inc.), or the like.
The average particle diameter of the carbon black particles which
are used for producing the black composite particles for the tread
rubber composition, using the silica particles (1) as core
particles, is preferably about 0.005 to 0.05 .mu.m, more preferably
about 0.010 to 0.035 .mu.m. When the average particle diameter
thereof is less than 0.005 .mu.m, the carbon black particles may be
difficult to handle because of too fine particles. When the average
particle diameter thereof is more than 0.05 .mu.m, a very large
mechanical shear force may be required to uniformly coat the carbon
black particles onto the coating layer composed of alkoxysilanes,
organosilane compounds or polysiloxanes because of too large
particle size thereof, resulting in industrially disadvantageous
process.
The carbon black in case of using the silica particles (1) as core
particles, are added in an amount of usually 1 to 500 parts by
weight, preferably 3 to 500 parts by weight, more preferably 50 to
500 parts by weight based on 100 parts by weight of the silica
particles (1).
When the amount of carbon black added is less than 1 part by
weight, it may be difficult to obtain composite particles having a
sufficiently low volume resistivity value and a sufficient
blackness because of too small amount of carbon black coated.
When the amount of carbon black added is more than 500 parts by
weight, although it is possible to obtain a black composite
particles having sufficient blackness and volume resistivity value,
the carbon black may tend to be desorbed from the silica particles
because of too large amount of the carbon black coated. As a
result, the obtained composite particles may tend to be
deteriorated in dispersibility in the tread rubber composition.
In case of using as core particles the white inorganic particles
(2) having a refractive index of less than 2.0 or the white
inorganic particles (3) having a refractive index of not less than
2.0, the black pigments such as carbon black and aniline black are
added in an amount of usually 1 to 500 parts by weight, preferably
2 to 400 parts by weight, more preferably 5 to 300 parts by weight
based on 100 parts by weight of the white inorganic particles. When
the amount of the black pigments added is out of the
above-specified range, it may be difficult to obtain the aimed
composite particles.
The heating temperature used in the drying and heating treatments
is usually 40 to 150.degree. C., preferably 60 to 120.degree. C.
The heating time is usually 10 minutes to 12 hours, preferably 30
minutes to 3 hours.
Meanwhile, in the case where alkoxysilanes or fluoroalkylsilanes
are used as the gluing agent, the gluing agent-coating layer
finally produced via these steps is composed of organosilane
compounds obtainable from the alkoxysilanes or fluorine-containing
organosilane compounds obtainable from the fluoroalkylsilanes.
The black composite particles produced by using the silica
particles (1) as core particles which are coated with a fatty acid,
a metal salt of fatty acid or a silane-based coupling agent, can be
produced by coating the above-produced black composite particles
with the fatty acid, the metal salt of fatty acid or the
silane-based coupling agent.
The coating of the black composite particles with the fatty acid,
the metal salt of fatty acid or the silane-based coupling agent may
be conducted by mechanically mixing and stirring the black
composite particles with the fatty acid, metal salt of fatty acid
or silane-based coupling agent while heating.
The fatty acid, the metal salt of fatty acid or the silane-based
coupling agent may be added in an amount of preferably 0.13 to 67
parts by weight based on 100 parts by weight of the black composite
particles. When the amount of the fatty acid, the metal salt of
fatty acid or the silane-based coupling agent added is in the range
of 0.13 to 67 parts by weight, the black composite particles can be
more improved in dispersibility in the tread rubber
composition.
The heating temperature used for coating the black composite
particles with the fatty acid, the metal salt of fatty acid or the
silane-based coupling agent, is preferably not less than 40.degree.
C., more preferably not less than 50.degree. C., most preferably
not less than 60.degree. C. The upper limit of the heating
temperature is a melting point or boiling point of the fatty acid,
the metal salt of fatty acid or the silane-based coupling agent
coated.
The white inorganic particles may be preliminarily coated, if
required, with a coat comprising at least one compound selected
from the group consisting of hydroxides of aluminum, oxides of
aluminum, hydroxides of silicon and oxides of silicon, prior to
mixing and stirring with the gluing agent.
The formation of the hydroxides and/or oxides of aluminum and/or
silicon coat may be conducted by adding an aluminum compound, a
silicon compound or both the aluminum and silicon compounds to a
water suspension containing the white inorganic particles; mixing
and stirring the resultant suspension, if required, followed by
adequately adjusting the pH value thereof, thereby coating the
white inorganic particles with an hydroxides and/or oxides of
aluminum and/or silicon coat comprising at least one compound
selected from the group consisting of hydroxides of aluminum,
oxides of aluminum, hydroxides of silicon and oxides of silicon;
and then subjecting the thus obtained particles to filtering-out,
water-washing, drying and pulverization. Further, if required, the
resultant particles may be subjected to deaeration, compaction or
the like.
Examples of the aluminum compound may include aluminum salts such
as aluminum acetate, aluminum sulfate, aluminum chloride and
aluminum nitrate, alkali aluminates such as sodium aluminate, or
the like.
Examples of the silicon compound may include water glass #3, sodium
orthosilicate, sodium metasilicate or the like.
The point of the present invention is that the composite particles
produced by coating black pigments onto the surface of the white
inorganic particle through the gluing agent-coating layer, can
exhibit an excellent dispersibility and an excellent light
resistance.
The point of the present invention is that the black composite
particles produced by coating carbon black onto the surface of
silica particles (1) through the coating layer comprising
organosilane compounds or polysiloxanes, can exhibit not only a
high blackness and a less discoloration upon exposure to light (an
excellent light resistance), but also a low volume resistivity
value and an excellent dispersibility.
The reason why the black composite particles produced by using the
silica particles (1) as core particles according to the present
invention can exhibit a high blackness, is considered by the
present inventors as follows. That is, since the silica particles
used as the core particles are extender pigments having a low
tinting strength and a low hiding power, and since the fine carbon
black particles usually behaving as agglomerates due to fine
particles can be uniformly and densely coated onto the surface of
the silica particle through the coating layer comprising
organosilane compounds obtainable from alkoxysilanes, or
polysiloxanes, the carbon black coated can exhibit its own
blackness without being eliminated by the hue of the core
particles.
The reason why the black composite particles produced by using the
silica particles (1) as core particles according to the present
invention can exhibit a less discoloration upon exposure to light,
is considered by the present inventors as follows. That is, it is
considered that the discoloration of the composite particles can be
prevented by coating the silica particles with the organosilane
compounds or polysiloxanes having an excellent light resistance,
and further by suppressing the surface activity of the silica
particles by formation of such a coating layer.
The reason why the black composite particles produced by using the
silica particles (1) as core particles according to the present
invention can exhibit an excellent dispersibility in the tread
rubber composition, is considered by the present inventors as
follows. That is, since the silica particles themselves tend to
show a poor compatibility with rubbers ordinarily used for tires
owing to existence of hydrophilic silanol groups on the surface
thereof and tend to be agglomerated together by formation of
hydrogen bonds between the silanol groups, it has been
conventionally difficult to uniformly disperse the silica particles
in the rubber composition for tires or the like. Whereas, in the
present invention, since carbon black capable of exhibiting an
excellent dispersibility in the rubber composition for tires or the
like is coated on the surface of the silica particles through the
coating layer comprising organosilane compounds or polysiloxanes,
the obtained black composite particles can be enhanced in
compatibility with the rubber component used in the tread rubber
composition. Further, since the amount of carbon black desorbed
from the surface of the composite particles is considerably
reduced, the black composite particles can be well dispersed in the
reaction system without disturbance by the desorbed carbon
black.
The reason why the tread rubber composition of the present
invention can exhibit an excellent light resistance, is considered
by the present inventors to be that the black composite particles
used as a filler for the tread rubber are excellent in light
resistance.
The reason why the tread rubber composition of the present
invention can exhibit a low electric resistance, is considered by
the present inventors to be that the black composite particles used
as a filler for the tread rubber have a high conductivity.
The reason why the tread rubber composition of the present
invention can exhibit excellent wear resistance and tensile
strength, is considered by the present inventors to be that the
black composite particles of the present invention can be uniformly
dispersed in the tread rubber composition.
Another point of the present invention is that the black composite
particles comprising white inorganic particles (2) having a
refractive index of less than 2.0, a gluing agent-coating layer
formed on the surface of the white inorganic particles (2), and a
black pigment coat coated onto the gluing agent-coating layer and
composed of aniline black or carbon black, are capable of not only
imparting thereto various functions such as electric properties
according to applications thereof, but also exhibiting excellent
light resistance, tinting strength, blackness and dispersibility in
vehicle.
An other point of the present invention is that the composite
particles comprising white inorganic particles (3) having a
refractive index of not less than 2.0, a gluing agent-coating layer
formed on the surface of the white inorganic particles (3), and a
black pigment coat coated onto the gluing agent-coating layer and
composed of aniline black or carbon black, are capable of not only
imparting thereto various functions such as electric properties
according to applications thereof, but also exhibiting excellent
ultraviolet light-shielding property, light resistance, tinting
strength and dispersibility in vehicle.
The reason why the black composite particles using the white
inorganic particles (2) having a refractive index of less than 2.0
as core particles can exhibit an excellent light resistance, is
considered by the present inventors to be that the black pigments
having a remarkably excellent light resistance as compared to dyes
are adhered onto the surface of the core particles having a
relatively excellent light resistance through the coating layer
composed of the gluing agent having an excellent light
resistance.
The reason why the composite particles produced by using the white
inorganic particles (3) having a refractive index of not less than
2.0 as core particles, can exhibit an excellent light resistance,
is considered by the present inventors to be that the composite
particles themselves are excellent in ultraviolet light-shielding
property, and the black pigments having a remarkably excellent
light resistance as compared to dyes are coated onto the core
particles having an excellent light resistance through the gluing
agent having an excellent light resistance.
The reason why the composite particles produced by using the white
inorganic particles (2) having a refractive index of less than 2.0
or the white inorganic particles (3) having a refractive index of
not less than 2.0 as core particles, can exhibit an excellent
dispersibility, is considered by the present inventors as follows.
That is, since the black pigments coated are prevented from being
desorbed from the surface of the core particles, the composite
particles of the present invention can be well dispersed in vehicle
without disturbance by the desorbed black pigments.
The reason why the composite particles produced by using the white
inorganic particles (3) having a refractive index of not less than
2.0 can exhibit an excellent ultraviolet light-shielding property,
is considered by the present inventors as follows. That is, the
white inorganic particles (3) having a refractive index of not less
than 2.0, in particular, titanium oxide and zinc oxide, can exhibit
a good absorptivity to wavelength of ultraviolet light region; the
gluing agent, in particular, organosilicon compounds, can exhibit a
low light transmittance to wavelength of ultraviolet light region
as compared to that of distilled water; and the black pigments, in
particular, carbon black, can exhibit a high absorptivity over a
wide wavelength region from ultraviolet to infrared, so that the
obtained composite particles can exhibit a higher ultraviolet
light-shielding property owing to the synergistic effect obtained
by the combination thereof.
The composite particles according to the present invention can
exhibit an excellent light resistance and an excellent
dispersibility, and therefore, are suitable as a filler for tread
rubber composition, paint and resin composition.
More specifically, the black composite particles produced by using
the silica particles (1) as core particles according to the present
invention can exhibit not only a less discoloration upon exposure
to light, but also a low volume resistivity value and an excellent
dispersibility and, therefore, are suitable as a filler or colorant
for tread rubber composition.
In addition, the rubber composition prepared by blending the above
black composite particles in rubber can exhibit not only a
discoloration upon exposure to light, but also a low electric
resistance and excellent wear resistance and tensile strength and,
therefore, are suitable as tread rubber composition.
The black composite particles produced by using the white inorganic
particles (2) having a refractive index of less than 2.0 according
to the present invention, are capable of not only imparting thereto
various functions such as electric properties according to
applications thereof, but also exhibiting excellent light
resistance, tinting strength and dispersibility in vehicle and,
therefore, suitable as black composite particles. Thus, the black
composite particles of the present invention can be suitably used
as colorants, fillers or the like for black pigments, black paints
and black resin compositions.
The composite particles produced by using the white inorganic
particles (3) having a refractive index (3) of not less than 2.0 as
core particles according to the present invention, are capable of
imparting thereto various functions according to applications
thereof, and exhibiting, in particular, an excellent ultraviolet
light-shielding property, as well as excellent light resistance,
handling property and dispersibility in vehicle.
EXAMPLES
The present invention is described in more detail by Examples and
Comparative Examples, but the Examples are only illustrative and,
therefore, not intended to limit the scope of the present
invention.
Various properties were evaluated by the following methods.
(1) The average particle size of the particles was expressed by an
average value of 350 particles observed on a micrograph.
(2) The specific surface area was expressed by the value measured
by a BET method.
(3) The amounts of Al and Si which were present on the surface of
white inorganic particle coated with an hydroxides and/or oxides of
aluminum and/or silicon coating material, were respectively
measured by a fluorescent X-ray spectroscopy device "3063 M-type"
(manufactured by RIGAKU DENKI KOGYO CO., LTD.) according to JIS
K0119 "General rule of fluorescent X-ray analysis".
(4) The amount of the gluing agent-coating layer formed onto the
surface of the white inorganic particles and the amount of the
black pigment coat formed onto the gluing agent-coating layer were
respectively expressed by the amount of carbon measured by "Horiba
Metal, Carbon and Sulfur Analyzer EMIA-2200 Model" (manufactured by
HORIBA SEISAKUSHO CO., LTD.).
(5) The desorption percentage (%) of black pigment desorbed from
the composite particles was measured by the following method. The
closer to 0% the desorption percentage, the smaller the amount of
the black pigment desorbed from the surface of the composite
particles.
That is, 3 g of the composite particles and 40 ml of ethanol were
placed in a 50-ml precipitation tube and then were subjected to
ultrasonic dispersion for 20 minutes. Thereafter, the obtained
dispersion was allowed to stand for 120 minutes, and black pigment
desorbed was separated from the composite particles on the basis of
the difference in specific gravity therebetween. Successively, the
obtained composite particles were mixed again with 40 ml of
ethanol, and then subjected to ultrasonic dispersion for 20
minutes. The obtained dispersion was allowed to stand for 120
minutes, and black pigment desorbed was separated from the
composite particles. The resultant composite particles were then
dried at 100.degree. C. for one hour, and the carbon content
thereof was measured by "Horiba Metal, Carbon and Sulfur Analyzer
EMIA-2200 Model" (manufactured by HORIBA SEISAKUSHO CO., LTD.). The
desorption percentage (%) of black pigment was calculated from the
thus measured values according to the following formula:
wherein W.sub.a represents an amount of black pigment initially
coated onto the composite particles; and We represents an amount of
black pigment still coated onto the composite particles after
desorption test.
(6) The hue of each of the white inorganic particles, black
pigments and composite particles was measured by the following
method.
That is, 0.5 g of each sample and 0.5 ml of castor oil were
intimately kneaded together by a Hoover's muller to form a paste.
4.5 g of clear lacquer was added to the obtained paste and was
intimately kneaded to form a paint. The obtained paint was applied
on a cast-coated paper by using a 150 .mu.m (6-mil) applicator to
produce a coating film piece (having a film thickness of about 30
.mu.m). The thus obtained coating film piece was measured by a
Multi-Spectro-Colour-Meter (manufactured by SUGA SHIKENKI CO.,
LTD.) to determine color specification values (L*, a* and b*
values) thereof according to JIS Z 8929. Meanwhile, the C* value
representing chroma is calculated according to the following
formula:
(7) The tinting strength of the composite particles was measured by
the following method.
That is, a primary color enamel and a vehicle enamel prepared by
the below-mentioned method were respectively applied on a
cast-coated paper by a 150 .mu.m (6-mil) applicator to produce
coating film pieces. The thus obtained coating film pieces were
measured by a multi-spectro-colour-meter "MSC-IS-2D" (manufactured
by SUGA TESTING MACHINES MANUFACTURING CO., LTD.) to determine L*
values thereof. The difference between the obtained L* values was
represented by a .DELTA.L* value.
Next, as a standard sample for the composite particles, a mixed
composite particles was prepared by simply mixing the black pigment
and the white inorganic particles at the same mixing ratio as used
for the production of the composite particles produced by using the
thus prepared mixed composite particles as standard sample, the
same procedure as defined above was conducted to prepare an primary
color enamel and a vehicle enamel, form coating film pieces and
measure L* values thereof. The difference between the L* values was
represented by a .DELTA.Ls* value.
From the obtained .DELTA.L* value of the composite particles and
.DELTA.Ls* value of the standard sample, the tinting strength (%)
was calculated according to the following formula:
Preparation of Primary Color Enamel:
10 g of the above sample particles, 16 g of an amino alkyd resin
and 6 g of a thinner were blended together. The resultant mixture
was added together with 90 g of 3 mm.phi. glass beads into a 140-ml
glass bottle, and then mixed and dispersed for 45 minutes by a
paint shaker. The obtained mixture was mixed with 50 g of an amino
alkyd resin, and further dispersed for 5 minutes by a paint shaker,
thereby obtaining an primary color enamel.
Preparation of Vehicle Enamel:
12 g of the above-prepared primary color enamel and 40 g of Aramic
White (titanium dioxide-dispersed amino alkyd resin) were blended
together, and the resultant mixture was mixed and dispersed for 15
minutes by a paint shaker, thereby preparing a vehicle enamel.
(8) The light resistances of the white inorganic particles, black
pigment and composite particles were measured by the following
method.
That is, the same primary color enamel as prepared above for the
measurement of tinting strength, was applied onto a cold-rolled
steel plate (0.8 mm.times.70 mm.times.150 mm; JIS G-3141) and dried
to form a coating film having a thickness of 150 .mu.m. One half of
the thus prepared test specimen was covered with a metal foil, and
an ultraviolet light was continuously irradiated over the test
specimen at an intensity of 100 mW/cm.sup.2 for 6 hours using "EYE
SUPER UV TESTER SUV-W13" (manufactured by IWASAKI DENKI CO., LTD.).
Then, the hues (L*, a* and b* values) of the metal foil-covered
non-irradiated portion and the UV-irradiated portion of the test
specimen were respectively measured. The .DELTA.E* value was
calculated from differences between the measured hue values of the
metal foil-covered non-irradiated portion and the UV-irradiated
portion according to the following formula:
wherein .DELTA.L* represents the difference between L* values of
the non-irradiated and UV-irradiated portions; .DELTA.a* represents
the difference between a* values of the non-irradiated and
UV-irradiated portions; and .DELTA.b* represents the difference
between b* values of the non-irradiated and UV-irradiated
portions.
(9) The repose angle (.degree.) of the composite particles was
measured using "powder tester" (manufactured by Hosokawa Micron
Co., Ltd.). The smaller the repose angle, the more excellent the
fluidity of the composite particles.
(10) The ultraviolet liqht-shieldinq property of the composite
particles was expressed by the light transmittance (%) at 360 nm of
a coating film obtained by applying a coating composition prepared
by the following method onto a 100 .mu.m-thick clear base film. The
light transmittance was measured by using a self-recording
photoelectric spectrophotometer "UV-2100" (manufactured by SHIMADZU
SEISAKUSHO CO., LTD.).
Preparation of Paint for Evaluation of Ultraviolet Light-Shielding
Property:
Sample particles, resins and solvents were charged at the following
weight ratio into a 250-ml glass bottle, and then mixed and
dispersed therein together with 160 g of 3 mm.phi. glass beads, for
120 minutes by a paint shaker, thereby preparing a paint for
evaluation of ultraviolet light-shielding property.
Composition of Paint for Evaluation of Ultraviolet Light-Shielding
Property:
Sample particles 4.0 parts by weight Melamine resin (SUPER
PECKAMINE 15.7 parts by weight J-820-60 (tradename) produced by
DAI-NIPPON INK KAGAKU KOGYO CO., LTD.) Alkyd resin (BECKOZOL
1307-60EL 31.5 parts by weight (tradename) produced by DAI-NIPPON
INK KAGAKU KOGYO CO., LTD.) Xylene 29.7 parts by weight Butanol 1.6
parts by weight
(11) The surface activity of the composite particles was evaluated
by measuring an amount of residual solvent by the following
method.
First, 1 g of sample particles and 10 g of a solvent (MEK) were
weighed. Then, the sample particles were immersed in the solvent
for 3 hours, and then air-dried for 24 hours. After further drying
the sample particles at 60.degree. C. for 24 hours, the carbon
content in the dried particles was measured by "Horiba Metal,
Carbon and Sulfur Analyzer EMIA-2200 Model" (manufactured by HORIBA
SEISAKUSHO CO., LTD.) to determine the amount of residual carbon
contained in the sample particles. The smaller the amount of
residual carbon, the smaller the amount of residual solvent and the
more effectively the surface activity of the particles can be
suppressed.
(12) The volume resistivity value of each of the silica particles,
black pigment, composite particles and tread rubber composition was
determined by measuring the electric resistance value of the
respective samples prepared by the following method.
In the case of each of the silica particles and composite
particles, 0.5 g of sample particles thereof were weighed, and
pressure-molded under a pressure of 1.372.times.10.sup.7 Pa (140
Kg/cm.sup.2) by a KBr tableting machine (manufactured by SHIMADZU
SEISAKUSHO CO., LTD.), thereby preparing a cylindrical test
specimen. In the case of the tread rubber composition, a resin
plate prepared by the below-mentioned method was punched into a
cylindrical test specimen.
Next, the thus prepared test specimen was exposed to the
environmental condition at a temperature of 25.degree. C. and a
relative humidity of 60% for not less than 12 hours, and then set
between a pair of stainless steel electrodes. The test specimen was
applied with a voltage of 15 V by using a Wheastone bridge ("TYPE
2768" manufactured by Yokogawa Hokushin Denki Co., Ltd.) to measure
an electric resistance value R (.OMEGA.) thereof.
Then, a top surface area A (cm.sup.2) and a thickness t.sub.0 (cm)
of the cylindrical test specimen were measured, and the volume
resistivity value (.OMEGA..multidot.cm) thereof was calculated by
inserting the measured values into the following formula:
(13-1) The light resistance of the tread rubber composition was
measured by the following method.
That is, one half of a resin plate prepared by the below-mentioned
method was covered with a metal foil, and an ultraviolet light was
continuously irradiated over the resin plate at an intensity of 100
mW/cm.sup.2 for 2 hours by using "EYE SUPER UV TESTER SUV-W13"
(manufactured by IWASAKI DENKI CO., LTD.). Then, the hues (L*, a*
and b* values) of the UV-irradiated portion and the metal
foil-covered non-irradiated portion of the resin plate were
respectively measured. The .DELTA.E* value was calculated from
differences between the measured hue values of the metal
foil-covered non-irradiated portion and the UV-irradiated portion
according to the following formula:
wherein .DELTA.L* represents the difference between L* values of
the non-irradiated and UV-irradiated portions; .DELTA.a* represents
the difference between a* values of the non-irradiated and
UV-irradiated portions; and .DELTA.b* represents the difference
between b* values of the non-irradiated and UV-irradiated
portions.
(13-2) The light resistances of the respective resin compositions
were measured by the following method.
That is, one half of the resin plate as prepared and used for
measuring the hues of the above tread rubber composition, was
covered with a metal foil, and an ultraviolet light was
continuously irradiated over the resin plate at an intensity of 100
mW/cm.sup.2 for 6 hours by using "EYE SUPER UV TESTER SUV-W13"
(manufactured by IWASAKI DENKI CO., LTD.). Then, the hues (L*, a*
and b* values) of the metal foil-covered non-irradiated portion and
the UV-irradiated portion of the resin plate were respectively
measured. The .DELTA.E* value was calculated from differences
between the measured hue values of the metal foil-covered
non-irradiated portion and the UV-irradiated portion according to
the following formula:
wherein .DELTA.L* represents the difference between L* values of
the non-irradiated and UV-irradiated portions; .DELTA.a* represents
the difference between a* values of the non-irradiated and
UV-irradiated portions; and .DELTA.b* represents the difference
between b* values of the non-irradiated and UV-irradiated
portions.
(14-1) The dispersibility of the composite particles in the tread
rubber composition was evaluated by visually counting the number of
undispersed aggregate particles on the surface of the obtained
tread rubber composition, and classifying the results into the
following five ranks. The Rank 5 represents the most excellent
dispersing condition.
Rank 5: No undispersed aggregate particles were recognized.
Rank 4: 1 to 4 undispersed aggregate particles per 1 cm.sup.2 were
recognized;
Rank 3: 5 to 9 undispersed aggregate particles per 1 cm.sup.2 were
recognized;
Rank 2: 10 to 49 undispersed aggregate particles per 1 cm.sup.2
were recognized;
Rank 1: Not less than 50 undispersed aggregate particles per 1
cm.sup.2 were recognized.
(14-2) The dispersibility of the composite particles in the resin
composition was evaluated by visually counting the number of
undispersed aggregate particles on the surface of the obtained
colored resin plate, and classifying the results into the following
five ranks. The Rank 5 represents the most excellent dispersing
condition.
Rank 5: No undispersed aggregate particles were recognized.
Rank 4: 1 to 4 undispersed aggregate particles per 1 cm.sup.2 were
recognized;
Rank 3: 5 to 9 undispersed aggregate particles per 1 cm.sup.2 were
recognized;
Rank 2: 10 to 49 undispersed aggregate particles per 1 cm.sup.2
were recognized;
Rank 1: Not less than 50 undispersed aggregate particles per 1
cm.sup.2 were recognized.
(15) The wear resistance of the tread rubber composition was
determined as follows. That is, the abrasion loss of the tread
rubber composition was measured by using "Lanborn abrasion tester"
under a load of 39.2 N (4.5 Kg) at a slip rate of 50% according to
JIS K 6264. The wear resistance was expressed by an index of the
measured abrasion loss which was obtained as a relative value
assuming that the abrasion loss of the tread rubber composition
obtained in Comparative Example 1 was 100. The larger the index of
the abrasion loss, the more excellent the wear resistance.
(16) The tensile strength of the tread rubber composition was
measured according to JIS K 6301.
(17) The hues of the solvent-based paint and water-based paint
using the composite particles were measured by the following
method.
That is, the respective paints prepared by the below-mentioned
methods, were applied onto a cold-rolled steel plate (0.8
mm.times.70 mm.times.150 mm; JIS G-3141) and dried to form a
coating film having a thickness of 150 .mu.m. The thus obtained
test specimens were measured by a Multi-Spectro-Colour-Meter
(manufactured by SUGA SHIKENKI CO., LTD.) to determine color
specification values (L*, a* and b* values) thereof according to
JIS Z 8929. Also, the hue of the resin composition tinted with the
composite particles was determined as follows. That is, the hue of
a colored resin plate prepared by the below-mentioned method was
measured by using a Multi-Spectro-Colour-Meter (manufactured by
SUGA SHIKENKI CO., LTD.) by the same method as described above.
(18) The gloss of the coating film was measured by irradiating
light at an incident angle of 60.degree., using "gloss meter
UGV-5D" (manufactured by SUGA TESTING MACHINES MANUFACTURING CO.,
LTD.). The higher the gloss, the more excellent the dispersibility
of the composite particles in the paint.
(19) The light resistances of coating films produced from the
respective paints, were measured by the following method.
That is, one half of the same test specimen as prepared and used
for measuring hues of the above paints, was covered with a metal
foil, and an ultraviolet light was continuously irradiated over the
test specimen at an intensity of 100 mW/cm.sup.2 for 6 hours using
"EYE SUPER UV TESTER SUV-W13" (manufactured by IWASAKI DENKI CO.,
LTD.). Then, the hues (L*, a* and b* values) of the metal
foil-covered non-irradiated portion and the UV-irradiated portion
of the test specimen were respectively measured. The .DELTA.E*
value was calculated from differences between the measured hue
values of the metal foil-covered non-irradiated portion and the
UV-irradiated portion according to the above-described formula.
.DELTA.E*=[(.DELTA.L*).sup.2 +(.DELTA.a*).sup.2 +(.DELTA.b*).sup.2
].sup.1/2
wherein .DELTA.L* represents the difference between L* values of
the non-irradiated and UV-irradiated portions; .DELTA.a* represents
the difference between a* values of the non-irradiated and
UV-irradiated portions; and .DELTA.b* represents the difference
between b* values of the non-irradiated and UV-irradiated
portions.
(20) The storage stability of the paint was measured by the
following method.
That is, the respective paints prepared by the below-mentioned
method were applied onto a cold-rolled steel plate (0.8 mm.times.70
mm.times.150 mm; JIS G-3141) and dried to form a coating film
having a thickness of 150 .mu.m. Then, the L*, a* and b* values of
the thus prepared coating film were measured. Separately, the
respective paints were allowed to stand at 25.degree. C. for one
week, and then applied onto the cold-rolled steel plate and dried
to form a similar coating film. The L*, a* and b* values of the
thus prepared coating film were also measured. The .DELTA.E* value
was calculated from the differences between the measured values
according to the following formula:
wherein .DELTA.L* represents the difference between L* values
before and after the standing test; .DELTA.a* represents the
difference between a* values before and after the standing test;
and .DELTA.b* represents the difference between b* values before
and after the standing test.
(21) The viscosity at 25.degree. C. of the paint prepared by the
below-mentioned method, was measured at a shear rate of 1.92
sec.sup.-1 by using an E-type viscometer (cone plate-type
viscometer) "EMD-R" (manufactured by TOKYO KEIKI CO., LTD.).
(22) The anti-aging property was determined as follows. That is, a
colored resin plate (1.5 cm in length.times.1.5 cm in width.times.1
mm in thickness) in which the composite particles were kneaded, was
heated at 190.degree. C. to measure an area S of a discolored
portion due to deteriorated resin. The ratio S/S.sub.0 of the
measured area S to a surface area S.sub.0 of the colored resin
plate before heating (1.5.times.1.5=2.25 cm.sup.2) was measured at
intervals of 5%. Specifically, the condition of
"(S/S.sub.0).times.100"=0% indicates no deterioration of resin,
while the condition of "(S/S.sub.0).times.100"=100% indicates
complete deterioration of resin.
Example 1
<Production of Black Composite Particles>
330 g of methyl hydrogen polysiloxane (tradename: "TSF484",
produced by GE TOSHIBA SILICONE CO., LTD.) was added to 11.0 kg of
silica particles (particle shape: granular shape; average particle
diameter: 0.022 .mu.m; BET specific surface area value: 193.8
m.sup.2 /g; volume resistivity value: 3.6.times.10.sup.7
.OMEGA..multidot.cm) while operating an edge runner, and the
resultant mixture was mixed and stirred for 40 minutes under a
linear load of 588 N/cm (60 Kg/cm) at a stirring speed of 22
rpm.
Then, 11.0 kg of fine carbon black particles (particle shape:
granular shape; particle diameter: 0.022 .mu.m; BET specific
surface area value: 134 m.sup.2 /g; blackness (L* value) of 16.6)
were added to the mixture for 10 minutes while operating the edge
runner, and the resultant mixture was mixed and stirred for 80
minutes under a linear load of 588 N/cm (60 Kg/cm) at a stirring
speed of 22 rpm, thereby coating carbon black onto the methyl
hydrogen polysiloxane coating layer formed on the respective silica
particles. The obtained particles were dried at 105.degree. C. for
60 minutes using a dryer, thereby obtaining black composite
particles.
The thus obtained black composite particles were in the form of
granular particles having an average particle diameter of 0.026
.mu.m, and had a BET specific surface area value of 124.2 m.sup.2
/g; a volume resistivity value of 7.4.times.10 .OMEGA..multidot.cm;
a light resistance (.DELTA.E* value) of 2.4; a blackness (L* value)
of 17.0; a carbon black desorption percentage of 7.8%; and a
coating amount of methyl hydrogen polysiloxane of 1.30% by weight
(calculated as Si). In addition, it was confirmed that the amount
of carbon black coated was 48.62% by weight (calculated as C;
corresponding to 100 parts by weight based on 100 parts by weight
of the silica particles). As a result of observing the micrograph,
since almost no carbon black was recognized from the micrograph, it
was confirmed that a substantially whole amount of the carbon black
used contributed to the formation of the carbon black coat on the
coating layer composed of methyl hydrogen polysiloxane.
Example 2
<Production of Tread Rubber Composition>
The following components were mixed and kneaded together at the
weight ratio shown below by an ordinary method using a Banbury
mixer and a kneading roller, thereby preparing a tread rubber
composition.
Tread Rubber Composition:
Styrene-butadiene copolymer 100.0 parts by weight Black composite
particles 40.0 parts by weight Zinc oxide 3.0 parts by weight
Stearic acid 2.0 parts by weight Anti-aging agent 2.0 parts by
weight Wax 1.0 part by weight Sulfur 1.8 parts by weight
Vulcanization-accelerator 0.8 part by weight
The thus obtained tread rubber composition was press-vulcanized at
160.degree. C. for 20 minutes, thereby preparing a test specimen.
The obtained test specimen was subjected to various tests.
As a result, it was confirmed that the obtained tread rubber
composition had a wear resistance of 110; an electric resistance
value of 3.2.times.10.sup.3 .OMEGA..multidot.cm; a tensile strength
of 24.8 MPa; and a light resistance (.DELTA.E* value) of 0.38.
Further, it was confirmed that the dispersing condition of the
composite particles in the tread rubber composition was Rank 5.
Example 3
<Production of Black Composite Particles>
350 g of methyl hydrogen polysiloxane (tradename: "TSF484",
produced by GE TOSHIBA SILICONE CO., LTD.) was added to 7.0 kg of
silica particles (particle shape: granular shape; average particle
diameter: 0.511 .mu.m; BET specific surface area value: 3.2 m.sup.2
/g; L* value: 93.8; a* value: 0.41; b* value: 0.76; C* value: 0.86;
refractive index: 1.42; light resistance: 5.56) while operating an
edge runner, and the resultant mixture was mixed and stirred for 30
minutes under a linear load of 588 N/cm (60 Kg/cm) at a stirring
speed of 22 rpm.
Then, 3.5 kg of black pigments C-2 (kind: aniline black; particle
shape: rod shape; average particle diameter: 0.31 .mu.m; BET
specific surface area value: 56.8 m.sup.2 /g; L* value: 16.20; a*
value: -1.03; b* value: 0.46; volume resistivity value:
3.6.times.10.sup.11 .OMEGA..multidot.cm; light resistance
(.DELTA.E* value): 15.21) were added to the mixture for 30 minutes
while operating the edge runner, and the resultant mixture was
mixed and stirred for 100 minutes under a linear load of 588 N/cm
(60 Kg/cm) at a stirring speed of 22 rpm, thereby coating the black
pigments C-2 onto the methyl hydrogen polysiloxane coating layer
formed on the respective silica particles. The obtained particles
were dried at 80.degree. C. for 60 minutes using a dryer, thereby
obtaining black composite particles.
The thus obtained black composite particles were in the form of
granular particles having an average particle diameter of 0.513
.mu.m, and had a BET specific surface area value of 12.9 m.sup.2
/g; a hue (L* value) of 17.57; a tinting strength of 137%; a repose
angle of 35.degree.; a volume resistivity value of
9.4.times.10.sup.10 .OMEGA..multidot.cm; a surface activity of
0.78%; a light resistance (.DELTA.E* value) of 2.14; a black
pigment desorption percentage of 6.4%; and a coating amount of
methyl hydrogen polysiloxane of 2.08% by weight (calculated as C).
In addition, it was confirmed that the amount of the black pigments
C-2 coated was 27.18% by weight (calculated as C; corresponding to
50 parts by weight based on 100 parts by weight of the silica
particles).
As a result of observing the micrograph, since almost no black
pigments C-2 were recognized from the micrograph, it was confirmed
that a substantially whole amount of the black pigments C-2 used
contributed to the formation of the black pigment coat on the
coating layer composed of methyl hydrogen polysiloxane. Further, it
was recognized that the black pigments C-2 coated no longer
maintained the particle shape and particle size of initially added
black pigments C-2, i.e., the black pigments C-2 were coated in the
form of much finer particles than the core particles to form a
black pigment coat on the surface of the respective core
particles.
Example 4
<Production of Solvent-Based Paint Containing Black Composite
Particles>
10 g of the black composite particles produced in Example 3, were
blended with an amino alkyd resin and a thinner at the following
weight ratio, and charged into a 140-ml glass bottle together with
90 g of 3 mm.phi. glass beads. Next, the obtained mixture was mixed
and dispersed for 90 minutes by a paint shaker, thereby preparing a
mill base.
Composition of Mill Base:
Black composite particles 12.2 parts by weight Amino alkyd resin
(AMILAC No. 1026, 19.5 parts by weight produced by KANSAI PAINT
CO., LTD.) Thinner 7.3 parts by weight
The above-prepared mill base was blended with an amino alkyd resin
at the following weight ratio, and the obtained mixture was further
mixed and dispersed for 15 minutes by a paint shaker, thereby
obtaining a solvent-based paint containing the black composite
particles.
Composition of Paint:
Mill base 39.0 parts by weight Amino alkyd resin (AMILAC No. 1026,
61.0 parts by weight produced by KANSAI PAINT CO., LTD.)
The thus obtained solvent-based paint exhibited a viscosity of
1,068 cP and a storage stability (.DELTA.E* value) of 0.91.
Next, the thus prepared solvent-based paint was applied onto a
cold-rolled steel plate (0.8 mm.times.70 mm.times.150 mm; JIS
G-3141) and dried to form a coating film having a thickness of 150
.mu.m. The obtained coating film showed a gloss of 92%, a blackness
(L* value) of 17.81 and a light resistance (.DELTA.E* value) of
2.44.
Example 5
<Production of Water-Based Paint Containing Composite
Particles>
7.62 g of the black composite particles obtained in Example 3, were
blended with a water-soluble alkyd resin and the like at the
following weight ratio, and charged into a 140-ml glass bottle
together with 90 g of 3 mm.phi. glass beads. Next, the obtained
mixture was mixed and dispersed for 90 minutes by a paint shaker,
thereby preparing a mill base.
Composition of Mill Base:
Black composite particles 12.4 parts by weight Water-soluble alkyd
resin (tradename: 9.0 parts by weight "S-118", produced by
DAI-NIPPON INK KAGAKU KOGYO CO., LTD.) Defoamer (tradename: "NOPCO
8034", 0.1 part by weight produced by SUN NOPCO CO., LTD.) Water
4.8 parts by weight Butyl cellosolve 4.1 parts by weight
The above-prepared mill base was blended with paint components
shown below at the following weight ratio, and the obtained mixture
was further mixed and dispersed for 15 minutes by a paint shaker,
thereby obtaining a water-based paint containing the black
composite particles.
Composition of Paint:
Mill base 30.4 parts by weight Water-soluble alkyd resin 46.2 parts
by weight (tradename: S-118, produced by DAI -NIPPON INK KAGAKU
KOGYO CO., LTD.) Water-soluble melamine resin 12.6 parts by weight
(tradename: S-695, produced by DAI-NIPPON INK KAGAKU KOGYO CO.,
LTD.) Defoamer (tradename: "NOPCO 8034", 0.1 part by weight
produced by SUN NOPCO CO., LTD.) Water 9.1 parts by weight Butyl
cellosolve 1.6 parts by weight
The thus obtained water-based paint exhibited a viscosity of 2,708
cP and a storage stability (.DELTA.E* value) of 0.89.
Next, the thus prepared water-based paint was applied onto a
cold-rolled steel plate (0.8 mm.times.70 mm.times.150 mm; JIS
G-3141) and dried to form a coating film having a thickness of 150
.mu.m. The obtained coating film showed a gloss of 90%, a blackness
(L* value) of 17.92 and a light resistance (.DELTA.E* value) of
2.40.
Example 6
<Production of Resin Composition>
2.5 g of the black composite particles obtained in Example 3, and
47. 5 g of polyvinyl chloride resin particles 103EP8D (produced by
NIPPON ZEON CO., LTD.) were weighed and charged into a 100-ml
beaker made of resins, and intimately mixed together by a spatula,
thereby obtaining mixed particles.
0.5 g of calcium stearate was added to the obtained mixed
particles. The mixed particles were intimately mixed and then
slowly supplied to hot rolls heated to 160.degree. C. whose
clearance was set to 0.2 mm, and continuously kneaded therebetween
until a uniform resin composition was produced. The resin
composition kneaded was separated from the hot rolls and used as a
raw material for forming a colored resin plate.
Next, the thus-produced resin composition was interposed between a
pair of surface-polished stainless steel plates, placed within a
hot press heated to 180.degree. C. and then subjected to a pressure
molding while applying a pressure of 98 MPa (1 ton/cm.sup.2)
thereto, thereby obtaining a colored resin plate having a thickness
of 1 mm. The thus-produced colored resin plate had a dispersing
condition of Rank 5, a hue (L* value) of 17.89 and a light
resistance (.DELTA.E* value) of 2.66.
The obtained colored resin plate was cut into test pieces of 1.5 cm
square. Three test pieces were placed in a Geer oven heated to
190.degree. C., and taken out therefrom one by one at 30 minute, 60
minute and 120 minute, respectively, after starting the examination
to examine the deterioration of resin. As a result, it was
confirmed that the degree of resin deterioration, i.e., the
anti-aging property (S/S.sub.0.times.100) was 0% after 30 minutes,
5% after 60 minutes and 5% after 120 minutes.
Example 7
<Production of Composite Particles>
20 kg of titanium oxide particles (particle shape: granular shape;
average particle diameter: 0.242 .mu.m; BET specific surface area
value: 11.6 m.sup.2 /g; L* value: 96.31, a* value: 1.06, b* value:
-1.66 and C* value: 1.97; refractive index: 2.71; light resistance
(.DELTA.E* value): 6.86) were deaggregated in 150 liters of pure
water using a stirrer, and further passed through "TK pipeline
homomixer" (manufactured by TOKUSHU KIKA KOGYO CO., LTD.) three
times, thereby obtaining a slurry containing the titanium oxide
particles.
Successively, the obtained slurry containing the titanium oxide
particles was passed through a transverse-type sand grinder
(tradename "MIGHTY MILL MHG-1.5L", manufactured by INOUE SEISAKUSHO
CO., LTD.) five times at an axis-rotating speed of 2,000 rpm,
thereby obtaining a slurry in which the titanium oxide particles
were dispersed.
The titanium oxide particles in the obtained slurry which remained
on a sieve of 325 meshes (mesh size: 44 .mu.m) was 0%. The slurry
was filtered and washed with water, thereby obtaining a wet cake
composed of the titanium oxide particles. The obtained wet cake
composed of the titanium oxide particles was dried at 120.degree.
C. Then, 7.0 kg of the dried particles were charged into an edge
runner "MPUV-2 Model" (tradename, manufactured by MATSUMOTO CHUZO
TEKKOSHO CO., LTD.), and mixed and stirred at 294 N/cm (30 Kg/cm)
for 30 minutes, thereby lightly deaggregating the particles.
Next, 140 g of methyl hydrogen polysiloxane (tradename: "TSF484",
produced by GE TOSHIBA SILICONE CO., LTD.) was added to the thus
obtained titanium oxide particles while operating an edge runner,
and the resultant mixture was mixed and stirred for 30 minutes
under a linear load of 588 N/cm (60 Kg/cm) at a stirring speed of
22 rpm.
Then, 7.0 kg of black pigments C-1 (kind: carbon black; particle
shape: granular shape; average particle diameter: 0.02 .mu.m; BET
specific surface area value: 134.0 m.sup.2 /g; L* value: 16.60;
volume resistivity value: 2.0.times.10.sup.2 .OMEGA..multidot.cm;
light resistance (.DELTA.E* value): 12.65) were added to the
mixture for 100 minutes while operating the edge runner, and the
resultant mixture was mixed and stirred for 60 minutes under a
linear load of 588 N/cm (60 Kg/cm) at a stirring speed of 22 rpm,
thereby coating the black pigments C-1 onto the methyl hydrogen
polysiloxane coating layer formed on the respective titanium oxide
particles. The obtained particles were dried at 105.degree. C. for
60 minutes using a dryer, thereby obtaining composite
particles.
The thus obtained composite particles were in the form of granular
particles having an average particle diameter of 0.246 .mu.m, and
had a BET specific surface area value of 15.1 m.sup.2 /g; a L*
value of 23.48; a tinting strength of 182%; a repose angle of 370;
a volume resistivity value of 5.9.times.10.sup.4
.OMEGA..multidot.cm; an ultraviolet light-shielding property of
94%; a surface activity of 6.9%; a light resistance (E* value) of
2.09; a black pigment desorption percentage of 8.1%; and a coating
amount of methyl hydrogen polysiloxane of 0.52% by weight
(calculated as C). In addition, it was confirmed that the amount of
the black pigments C-1 coated was 48.76% by weight (calculated as
C; corresponding to 100 parts by weight based on 100 parts by
weight of the titanium oxide particles).
As a result of observing the micrograph, since almost no black
pigments C-1 were recognized from the micrograph, it was confirmed
that a substantially whole amount of the black pigments C-1 used
contributed to the formation of the black pigment coat on the
coating layer composed of methyl hydrogen polysiloxane.
Example 8
<Production of Solvent-Based Paint Containing Composite
Particles>
10 g of the composite particles produced in Example 7, were blended
with an amino alkyd resin and a thinner at the following weight
ratio, and charged into a 140-ml glass bottle together with 90 g of
3 mm.phi. glass beads. Next, the obtained mixture was mixed and
dispersed for 90 minutes by a paint shaker, thereby preparing a
mill base.
Composition of Mill Base:
Composite particles 12.2 parts by weight Amino alkyd resin (AMILAC
No. 1026, 19.5 parts by weight produced by KANSAI PAINT CO., LTD.)
Thinner 7.3 parts by weight
The above-prepared mill base was blended with an amino alkyd resin
at the following weight ratio, and the obtained mixture was further
mixed and dispersed for 15 minutes by a paint shaker, thereby
obtaining a solvent-based paint containing the composite
particles.
Composition of Paint:
Mill base 39.0 parts by weight Amino alkyd resin (AMILAC No. 1026,
61.0 parts by weight produced by KANSAI PAINT CO., LTD.)
The thus obtained solvent-based paint exhibited a viscosity of
1,024 cP and a storage stability (.DELTA.E* value) of 0.90.
Next, the thus prepared solvent-based paint was applied onto a
cold-rolled steel plate (0.8 mm.times.70 mm.times.150 mm; JIS
G-3141) and dried to form a coating film having a thickness of 150
.mu.m. The obtained coating film showed a gloss of 95%, a L* value
of 24.31 and a light resistance (.DELTA.E* value) of 2.32.
Example 9
<Production of Water-Based Paint Containing Composite
Particles>
7.62 g of the composite particles obtained in Example 7, were
blended with a water-soluble alkyd resin and the like at the
following weight ratio, and charged into a 140-ml glass bottle
together with 90 g of 3 mm.phi. glass beads. Next, the obtained
mixture was mixed and dispersed for 90 minutes by a paint shaker,
thereby preparing a mill base.
Composition of Mill Base:
Composite particles 12.4 parts by weight Water-soluble alkyd resin
9.0 parts by weight (tradename: "S-118", produced by DAI-NIPPON INK
KAGAKU KOGYO CO., LTD.) Defoamer (tradename: 0.1 part by weight
"NOPCO 8034", produced by SUN NOPCO CO., LTD.) Water 4.8 parts by
weight Butyl cellosolve 4.1 parts by weight
The above-prepared mill base was blended with paint components
shown below at the following weight ratio, and the obtained mixture
was further mixed and dispersed for 15 minutes by a paint shaker,
thereby obtaining a water-based paint containing the composite
particles.
Composition of Paint:
Mill base 30.4 parts by weight Water-soluble alkyd resin 46.2 parts
by weight (tradename: S-118, produced by DAI-NIPPON INK KAGAKU
KOGYO CO., LTD.) Water-soluble melamine resin 12.6 parts by weight
(tradename: S-695, produced by DAI-NIPPON INK KAGAKU KOGYO CO.,
LTD.) Defoamer (tradename: 0.1 part by weight "NOPCO 8034",
produced by SUN NOPCO CO., LTD.) Water 9.1 parts by weight Butyl
cellosolve 1.6 parts by weight
The thus obtained water-based paint exhibited a viscosity of 2,418
cP and a storage stability (.DELTA.E* value) of 0.90.
Next, the thus prepared water-based paint was applied onto a
cold-rolled steel plate (0.8 mm.times.70 mm.times.150 mm; JIS
G-3141) and dried to form a coating film having a thickness of 150
.mu.m. The obtained coating film showed a gloss of 90%, a L* value
of 24.83 and a light resistance (.DELTA.E* value) of 2.30.
Example 10
<Production of Resin Composition>2.5 g of the composite
particles obtained in Example 7, and 47. 5 g of polyvinyl chloride
resin particles 103EP8D (produced by NIPPON ZEON CO., LTD.) were
weighed and charged into a 100-ml beaker made of resins, and
intimately mixed together by a spatula, thereby obtaining mixed
particles.
0.5 g of calcium stearate was added to the obtained mixed
particles. The mixed particles were intimately mixed and then
slowly supplied to hot rolls heated to 160.degree. C. whose
clearance was set to 0.2 mm, and continuously kneaded therebetween
until a uniform resin composition was produced. The resin
composition kneaded was separated from the hot rolls and used as a
raw material for forming a colored resin plate.
Next, the thus-produced resin composition was interposed between a
pair of surface-polished stainless steel plates, placed within a
hot press heated to 180.degree. C. and then subjected to a pressure
molding while applying a pressure of 98 MPa (1 ton/cm.sup.2)
thereto, thereby obtaining a colored resin plate having a thickness
of 1 mm. The thus-produced colored resin plate had a dispersing
condition of Rank 5, a hue (L* value) of 25.11 and a light
resistance (.DELTA.E* value) of 2.46.
The obtained colored resin plate was cut into test pieces of 1.5 cm
square. Three test pieces were placed in a Geer oven heated to
190.degree. C., and taken out therefrom one by one at 30 minute, 60
minute and 120 minute, respectively, after starting the examination
to examine the deterioration of resin. As a result, it was
confirmed that the degree of resin deterioration, i.e., the
anti-aging property (S/S.sub.0.times.100) was 0% after 30 minutes,
5% after 60 minutes and 5% after 120 minutes.
Core Particles 1 to 3:
Various silica particles as core particles 1 to 3 having properties
shown in Table 1 were prepared.
Core Particles 4:
A slurry containing silica particles was obtained by dispersing 20
kg of silica particles (deaggregated core particles 1) in 150
liters of water. The pH value of the thus obtained slurry
containing the silica particles was adjusted to 10.5 by using an
aqueous sodium hydroxide solution, and then the concentration of
the slurry was adjusted to 98 g/liter by adding water thereto.
After 150 liters of the slurry was heated to 60.degree. C., 2722 ml
of a 1.0 mol/liter NaAlO.sub.2 solution (corresponding to 0.5% by
weight (calculated as Al) based on the weight of the silica
particles) was added to the slurry. After allowing the obtained
slurry to stand for 30 minutes, the pH value of the slurry was
adjusted to 7.5 by using acetic acid. After further allowing the
resultant slurry to stand for 30 minutes, the slurry was subjected
to filtration, washing with water, drying and pulverization,
thereby obtaining the silica particles coated with hydroxides of
aluminum.
The essential production conditions and various properties of the
obtained surface-treated silica particles are shown in Table 2.
Core particles 5 and 6:
The same procedure as defined for the production of the above core
particles 4, was conducted except that the core particles 5 and 6
were respectively used instead of the core particles 1, and kinds
and amounts of hydroxides and/or oxides of aluminum and/or silicon
coats were changed variously, thereby obtaining silica particles
coated with the hydroxides and/or oxides of aluminum and/or silicon
coat.
The essential production conditions and various properties of the
obtained surface-treated silica particles are shown in Table 2.
Meanwhile, in Tables, "A" as described in "kind of coating material
used in surface-treating step" represents hydroxides of
aluminum.
Examples 11 to 16 and Comparative Examples 1 to 2:
The same procedure as defined in Example 1 was conducted except
that kinds of core particles; use or non-use, kinds and amounts of
alkoxysilanes or polysiloxanes added; conditions for edge runner
treatment used in the coating step with alkoxysilanes or
polysiloxanes; kinds and amounts of fine carbon black particles
added; and conditions for edge runner treatment used in the carbon
black-coating step, were changed variously, thereby obtaining black
composite pigments. In the case of the black composite particles
obtained in Examples 11 to 16, as a result of observing the
micrograph, since almost no carbon black was recognized from the
micrograph, it was confirmed that a substantially whole amount of
the carbon black used contributed to the formation of the carbon
black coat on the coating layer composed of alkoxysilanes or
polysiloxanes.
Various properties of the fine carbon black particles A to C used
are shown in Table 3.
The essential production conditions are shown in Table 4, and
various properties of the obtained composite particles are shown in
Table 5.
Comparative Example 3
(Follow-Us Test of Example 1 of Japanese Patent No. 3160552)
The silica particles as core particles 1 were charged into a rotary
continuous-heating furnace. An inside of the furnace was fully
purged with nitrogen to adjust the oxygen concentration therein to
not more than 0.3% by volume. Then, while flowing a mixed gas of
nitrogen and propane (a mixing volume ratio: 10:1) through the
furnace, the inside of the furnace was heated to 900.degree. C. to
thermally decompose the propane, thereby forming a carbon coat on
the surface of the respective silica particles. It was confirmed
that the amount of the carbon coat was 20 parts by weight based on
100 parts by weight of the silica particles.
Various properties of the obtained black silica particles are shown
in Table 5.
Example 17
20 g of calcium stearate was added to 2 kg of the black composite
particles, and the resultant mixture was heated up to 120.degree.
C. for 30 minutes while stirring by a Henschel mixer. The mixture
was held under the above condition for 45 minutes, and then cooled
to room temperature for 30 minutes, thereby obtaining
surface-coated black composite particles.
The essential production conditions are shown in Table 6, and
various properties of the obtained surface-coated composite
particles are shown in Table 7.
Examples 18 and 19
The same procedure as defined in Example 17 was conducted except
that kinds of composite particles; kinds and amounts of fatty acid,
metal salt of fatty acid or coupling agent coated; and kneading
temperature and kneading time for the coating step using Henschel
mixer, were changed variously, thereby obtaining surface-coated
composite particles.
The essential production conditions are shown in Table 6, and
various properties of the obtained composite particles are shown in
Table 7.
Examples 20 to 28 and Comparative Examples 4 to 8
The same procedure as defined in Example 2 was conducted except
that kinds of fillers were changed variously, thereby obtaining
tread rubber compositions.
The essential production conditions and various properties of the
obtained tread rubber compositions are shown in Table 8.
Core Particles 7 to 12:
Various white inorganic particles as core particles 7 to 10 having
properties shown in Table 9 were prepared. In addition, for
comparative purpose, iron oxide particles as core particles 11 and
12 were prepared.
Core Particles 13:
A slurry containing silica particles was obtained by dispersing 20
kg of silica particles (core particles 7) in 150 liters of water.
The pH value of the thus obtained re-dispersed slurry containing
the silica particles was adjusted to 10.5 by using an aqueous
sodium hydroxide solution, and then the concentration of the slurry
was adjusted to 98 g/liter by adding water thereto. After 150
liters of the slurry was heated to 60.degree. C., 2722 ml of a 1.0
mol/liter sodium aluminate solution (corresponding to 0.5% by
weight (calculated as Al) based on the weight of the silica
particles) was added to the slurry. After allowing the obtained
slurry to stand for 30 minutes, the pH value of the slurry was
adjusted to 7.5 by using acetic acid. After further allowing the
resultant slurry to stand for 30 minutes, the slurry was subjected
to filtration, washing with water, drying and pulverization,
thereby obtaining the silica particles coated with hydroxides of
aluminum.
The essential production conditions are shown in Table 10, and
various properties of the obtained surface-treated silica particles
are shown in Table 11.
Core Particles 14 to 16:
The same procedure as defined for the production of the above core
particles 13, was conducted except that the white inorganic
particles as core particles 8 to 10 were respectively used instead
of the core particles 7, and kinds and amounts of surface coating
materials were changed variously, thereby obtaining white inorganic
particles whose surface was coated with the coating material.
The essential production conditions are shown in Table 10, and
various properties of the obtained surface-treated white inorganic
particles are shown in Table 11.
Meanwhile, in Tables, "A" and "S" as described in "kind of coating
material used in surface-treating step" represent hydroxides of
aluminum and oxides of silicon, respectively.
Black Pigments:
Black pigments having properties as shown in Table 12 were
prepared.
Examples 29 to 36 and Comparative Examples 9 to 12
The same procedure as defined in Example 3 was conducted except
that kinds and amounts of additives added in coating step with
gluing agent, linear load and treating time for edge runner
treatment used in the coating step with gluing agent, kinds and
amounts of black pigments coated in black pigment-coating step, and
linear load and treating time for edge runner treatment used in the
black pigment-coating step, were changed variously, thereby
obtaining black composite particles.
The essential production conditions are shown in Table 13, and
various properties of the obtained black composite particles are
shown in Table 14.
Meanwhile, in Example 29, the black pigments C-1 were added five
times in an amount of 20.0 parts by weight each, to 100.0 parts by
weight of the core particles such that the total amount of the
black pigments C-1 added was 100.0 parts by weight. In Example 33,
150.0 parts by weight of the black pigments C-2 were continuously
added to 100.0 parts by weight of the core particles for 150
minutes.
Examples 37 to 44 and Comparative Examples 13 to 22
<Solvent-Based Paint>
The same procedure as defined in Example 4 was conducted except
that kinds and amounts of black composite particles and black
pigments added were changed variously, thereby obtaining
solvent-based paints.
Various properties of the obtained solvent-based paints and various
properties of coating films obtained therefrom are shown in Tables
15 and 16.
Examples 45 to 52 and Comparative Examples 23 to 32
<Water-Based Paint>
The same procedure as defined in Example 5 was conducted except
that kinds and amounts of the black composite particles and black
pigments added were changed variously, thereby obtaining
water-based paints.
Various properties of the obtained water-based paints and various
properties of coating films obtained therefrom are shown in Tables
17 and 18.
Examples 53 to 60 and Comparative Examples 33 to 42
<Resin Composition>
The same procedure as defined in Example 6 was conducted except
that kinds and amounts of the black composite particles and black
pigments added were changed variously, thereby obtaining resin
compositions.
The essential production conditions and various properties of the
obtained resin compositions are shown in Tables 19 and 20.
Core Particles 17 to 19:
Various white inorganic particles as core particles 17 to 19 having
properties shown in Table 21 were prepared.
Core Particles 20:
A slurry containing titanium oxide particles was obtained by
dispersing 20 kg of titanium oxide particles (core particles 17) in
150 liters of water. The pH value of the thus obtained re-dispersed
slurry containing the titanium oxide particles was adjusted to 10.5
by using an aqueous sodium hydroxide solution, and then the
concentration of the slurry was adjusted to 98 g/liter by adding
water thereto. After 150 liters of the slurry was heated to
60.degree. C., 5444 ml of a 1.0 mol/liter sodium aluminate solution
(corresponding to 1.0% by weight (calculated as Al) based on the
weight of the titanium oxide particles) was added to the slurry.
After allowing the obtained slurry to stand for 30 minutes, the pH
value of the slurry was adjusted to 7.5 by using acetic acid. After
further allowing the resultant slurry to stand for 30 minutes, the
slurry was subjected to filtration, washing with water, drying and
pulverization, thereby obtaining the titanium oxide particles
coated with hydroxides of aluminum.
The essential production conditions are shown in Table 22, and
various properties of the obtained surface-treated titanium oxide
particles are shown in Table 23.
Core Particles 21 and 22:
The same procedure as defined for the production of the above core
particles 20, was conducted except that the white inorganic
particles as core particles 18 and 19 were respectively used
instead of the core particles 17, and kinds and amounts of surface
coating materials were changed variously, thereby obtaining white
inorganic particles whose surface was coated with the coating
material.
The essential production conditions are shown in Table 22, and
various properties of the obtained surface-treated white inorganic
particles are shown in Table 23.
Meanwhile, in Tables, "A" and "S" as described in "kind of coating
material used in surface-treating step" represent hydroxides of
aluminum and oxides of silicon, respectively.
Black Pigments:
Black pigments having properties as shown in Table 12 were
prepared.
Examples 61 to 66 and Comparative Examples 43 to 47
The same procedure as defined in Example 7 was conducted except
that kinds and amounts of additives added in coating step with
gluing agent, linear load and treating time for edge runner
treatment used in the coating step with gluing agent, kinds and
amounts of black pigments coated in black pigment-coating step, and
linear load and treating time for edge runner treatment used in the
black pigment-coating step, were changed variously, thereby
obtaining composite particles.
The essential production conditions are shown in Table 24, and
various properties of the obtained composite particles are shown in
Table 25.
Meanwhile, in Example 62, the black pigments C-2 were added five
times in an amount of 20.0 parts by weight each, to 100.0 parts by
weight of the core particles such that the total amount of the
black pigments C-2 added was 100.0 parts by weight. In Example 64,
75.0 parts by weight of the black pigments C-2 were continuously
added to 100.0 parts by weight of the core particles for 75
minutes.
Examples 67 to 72 and Comparative Examples 48 to 55
<Solvent-Based Paint>
The same procedure as defined in Example 8 was conducted except
that kinds and amounts of composite particles and black pigments
added were changed variously, thereby obtaining solvent-based
paints.
Various properties of the obtained solvent-based paints and various
properties of coating films obtained therefrom are shown in Tables
26 and 27.
Examples 73 to 78 and Comparative Examples 56 to 63
<Water-Based Paint>
The same procedure as defined in Example 9 was conducted except
that kinds and amounts of composite particles and black pigments
added were changed variously, thereby obtaining water-based
paints.
Various properties of the obtained water-based paints and various
properties of coating films obtained therefrom are shown in Tables
28 and 29.
Examples 79 to 84 and Comparative Examples 64 to 71
<Resin Composition>
The same procedure as defined in Example 10 was conducted except
that kinds and amounts of composite particles and black pigments
added were changed variously, thereby obtaining resin
compositions.
The essential production conditions and various properties of the
obtained resin compositions are shown in Tables 30 and 31.
TABLE 1 Properties of silica particles BET Average specific Volume
particle surface resistivity Kind of core diameter area value
particles Shape (.mu.m) value (m.sup.2 /g) (.OMEGA. .multidot. cm)
Core Granular 0.021 198.3 2.3 .times. 10.sup.7 particles 1 Core
Granular 0.014 254.6 1.6 .times. 10.sup.6 particles 2 Core Granular
0.084 100.3 5.6 .times. 10.sup.7 particles 3
TABLE 2 Properties of surface-treated silica particles
Surface-treating step Average Volume Kind of Additives Coating
material particle BET specific resistivity Core core Calculated
Amount Calculated Amount diameter surface area value particles
particles Kind as (wt. %) Kind as (wt. %) (.mu.m) value (m.sup.2
/g) (.OMEGA. .multidot. cm) Core Core Sodium Al 0.5 A Al 0.49 0.022
186.3 6.8 .times. 10.sup.7 particles 4 particles 1 aluminate Core
Core Aluminum Al 2.0 A Al 1.96 0.015 211.4 2.6 .times. 10.sup.7
particles 5 particles 2 sulfate Core Core Aluminum Al 5.0 A Al 4.76
0.086 96.5 8.3 .times. 10.sup.7 particles 6 particles 3 sulfate
TABLE 3 Properties of fine carbon black particles BET specific Kind
of Average surface fine carbon particle area Blackness black
diameter value (L* value) particles Shape (.mu.m) (m.sup.2 /g) (-)
Carbon Granular 0.022 133.5 14.6 black A Carbon Granular 0.015
265.3 15.2 black B Carbon Granular 0.030 84.6 17.0 black C
TABLE 4 Production of black composite particles Coating step with
alkoxysilanes or polysiloxanes Coating step with carbon black
Coating Amount Additives amount coated Examples Amount (calcu-
(calcu- and Kind of added Edge runner treatment lated Carbon black
Edge runner treatment lated Comparative core (wt. Linear load Time
as C) Amount added Linear load Time as C) Examples particles Kind
part) (N/cm) (Kg/cm) (min) (wt. %) Kind (wt. part) (N/cm) (Kg/cm)
(min) (wt. %) Example 11 Core Methyl hydrogen 3.0 441 45 20 0.78 A
50.0 588 60 60 33.11 particles 1 polysiloxane Example 12 Core
Phenyl 2.0 588 60 20 0.70 B 100.0 588 60 80 49.72 particles 2
triethoxysilane Example 13 Core Methyl 5.0 588 60 30 0.31 C 150.0
735 75 120 58.92 particles 3 triethoxysilane Example 14 Core Methyl
hydrogen 1.5 294 30 30 0.39 A 20.0 588 60 50 16.55 particles 4
polysiloxane Example 15 Core Methyl 3.0 735 75 30 0.25 B 80.0 588
60 60 44.17 particles 5 trimethoxysilane Example 16 Core Methyl 2.0
294 30 30 0.13 C 160.0 735 75 120 61.02 particles 6 triethoxysilane
Comparative Core -- -- -- -- -- -- A 50.0 588 60 60 33.08 Example 1
particles 1 Comparative Core Methyl hydrogen 3.0 588 60 20 0.78 A
0.5 588 60 60 0.48 Example 2 particles 1 polysiloxane
TABLE 5 Properties of black composite particles Average Volume
Light Carbon black Examples and particle BET specific resistivity
Blackness resistance desorption Comparative diameter surface area
value (L* value) (.DELTA.E* value) percentage Examples (.mu.m)
value (m.sup.2 /g) (.OMEGA. .multidot. cm) (-) (-) (%) Example 11
0.023 154.3 1.6 .times. 10.sup.2 16.4 2.9 5.5 Example 12 0.018
196.4 8.1 .times. 10.sup.1 16.2 2.5 6.6 Example 13 0.090 86.3 9.6
.times. 10.sup.1 17.3 2.3 8.3 Example 14 0.023 171.2 4.3 .times.
10.sup.2 19.1 2.2 2.1 Example 15 0.018 183.8 6.4 .times. 10.sup.1
16.5 1.7 3.4 Example 16 0.092 81.6 8.1 .times. 10.sup.1 17.3 1.4
4.2 Comparative 0.022 170.1 2.8 .times. 10.sup.3 22.6 6.2 81.6
Example 1 Comparative 0.021 188.7 4.8 .times. 10.sup.6 35.8 10.3 --
Example 2 Comparative 0.022 175.9 8.7 .times. 10.sup.2 21.8 6.5
73.9 Example 3
TABLE 6 Coating step with fatty acid, fatty acid metal salt or
coupling agent Black composite particles Additives Production of
surface-coated black Kind of Amount composite particles black added
Kneading Kneading Coating amount composite (wt. temperature time
(calculated as C) Examples particles Kind part) (.degree. C.) (min)
(wt. %) Example 17 Example 11 Calcium stearate 1.0 120 45 0.70
Example 18 Example 14 Magnesium 1.5 120 30 1.05 stearate Example 19
Example 13 .gamma.-mercaptopropyl 1.0 80 30 0.35
trimethoxysilane
TABLE 7 Properties of surface-coated black composite particles
Average BET specific particle surface area Blackness Volume
resistivity Light resistance diameter value (L* value) value
(.DELTA.E* value) Examples (.mu.m) (m.sup.2 /g) (-) (.OMEGA.
.multidot. cm) (-) Example 17 0.023 149.1 16.5 2.2 .times. 10.sup.2
2.6 Example 18 0.023 163.8 19.3 4.6 .times. 10.sup.2 2.0 Example 19
0.090 81.4 17.4 1.7 .times. 10.sup.2 2.1
TABLE 8 Properties of tread rubber composition Production of tread
rubber composition Electric Examples and Fillers Dispersing Wear
resistance Light resistance Comparative Amount blended condition
resistance value Tensile strength (.DELTA.E* value) Examples Kind
(wt. part) (-) (-) (.OMEGA. .multidot. cm) (MPa) (-) Example 20
Example 11 50.0 5 106 3.6 .times. 10.sup.4 24.5 4.2 Example 21
Example 12 50.0 5 108 4.1 .times. 10.sup.3 24.9 3.8 Example 22
Example 13 50.0 4 112 7.2 .times. 10.sup.2 25.1 3.5 Example 23
Example 14 50.0 5 111 6.9 .times. 10.sup.4 23.9 4.1 Example 24
Example 15 50.0 5 113 8.8 .times. 10.sup.3 24.9 3.4 Example 25
Example 16 50.0 5 117 4.1 .times. 10.sup.2 25.5 2.9 Example 26
Example 17 50.0 5 112 9.5 .times. 10.sup.3 24.7 3.9 Example 27
Example 18 50.0 5 114 3.3 .times. 10.sup.3 25.0 3.6 Example 28
Example 19 50.0 5 119 6.7 .times. 10.sup.2 25.8 3.2 Comparative
Carbon black A 50.0 4 100 2.8 .times. 10.sup.2 25.0 5.3 Example 4
Comparative Core particles 1 50.0 1 84 .sup. 1.9 .times. 10.sup.12
22.5 -- Example 5 Comparative Comparative Example 1 50.0 2 93 6.5
.times. 10.sup.5 22.9 6.5 Example 6 Comparative Comparative Example
2 50.0 1 87 .sup. 4.4 .times. 10.sup.11 22.6 10.9 Example 7
Comparative Comparative Example 3 50.0 2 92 7.9 .times. 10.sup.5
22.8 7.0 Example 8
TABLE 9 Kind of core Properties of white inorganic particles
particles Kind Shape Core Silica Spherical particles 7 Core Silica
Spherical particles 8 Core Precipitated Granular particles 9 barium
sulfate Core Calcium Granular particles 10 carbonate Core
Mn-containing Granular particles 11 hematite particles Core
Magnetite Spherical particles 12
TABLE 9 Properties of white inorganic particles Average particle
BET specific Hue Light resistance Kind of core diameter surface
area value L* value a* value b* value C* value Refractive index
(.DELTA.E* value) particles (.mu.m) (m.sup.2 /g) (-) (-) (-) (-)
(-) (-) Core 3.915 0.7 95.28 0.16 0.88 0.89 1.42 5.74 particles 7
Core 0.603 3.8 96.13 0.08 0.96 0.96 1.40 5.38 particles 8 Core
0.059 21.3 91.62 0.31 1.03 1.08 1.62 5.92 particles 9 Core 0.140
18.6 93.65 0.06 1.11 1.11 1.49 7.01 particles 10 Core 0.323 3.1
22.44 4.28 3.01 5.23 2.92 7.22 particles 11 Core 0.230 11.8 20.10
1.53 2.16 2.65 2.42 6.69 particles 12
TABLE 10 Surface-treating step Kind of Additives Coating material
Core core Calculated Amount Calculated Amount particles particles
Kind as (wt. %) Kind as (wt. %) Core Core Sodium Al 0.5 A Al 0.49
particles 13 particles 7 aluminate Core Core Aluminum Al 2.0 A Al
1.96 particles 14 particles 8 sulfate Core Core Sodium Al 2.0 A Al
1.93 particles 15 particles 9 aluminate Water SiO.sub.2 0.5 S
SiO.sub.2 0.47 glass #3 Core Core Water SiO.sub.2 1.0 S SiO.sub.2
0.98 particles 16 particles 10 glass #3
TABLE 11 Properties of surface-treated white inorganic particles
Average particle BET specific Hue Light resistance Kind of core
diameter surface area value L* value a* value b* value C* value
Refractive index (.DELTA.E* value) particles (.mu.m) (m.sup.2 /g)
(-) (-) (-) (-) (-) (-) Core 3.916 1.2 94.95 0.12 0.94 0.95 1.42
5.56 particles 13 Core 0.610 4.6 93.15 0.11 0.93 0.94 1.41 5.08
particles 14 Core 0.061 21.9 91.03 0.44 0.81 0.92 1.62 5.32
particles 15 Core 0.141 17.9 92.16 0.08 1.10 1.10 1.49 6.98
particles 16
TABLE 12 Properties of black pigments BET Average specific particle
surface Hue Volume resistivity Light resistance Black diameter area
value L* value a* value b* value value (.DELTA.E* value) pigments
Kind Shape (.mu.m) (m.sup.2 /g) (-) (-) (-) (.OMEGA. .multidot. cm)
(-) Black Carbon Granular 0.02 134.0 16.60 0.93 0.73 2.0 .times.
10.sup.2 12.65 pigments black C-1 Black Aniline Rod- 0.31 56.8
16.20 -1.03 0.46 .sup. 3.6 .times. 10.sup.11 15.21 pigments black
shaped C-2
TABLE 13 Production of black composite particles Coating step with
Coating step with Coating step with gluing agent black pigments
gluing agent Coating Amount Additives Edge runner amount Pigments
coated Examples Amount treatment (calcu- Amount Edge runner (calcu-
and Kind of added Linear lated added treatment lated Comparative
core (wt. load Time as C) (wt. Linear load Time as C) Examples
particles Kind part) (N/cm) (Kg/cm) (min) (wt. %) Kind part) (N/cm)
(Kg/cm) (min) (wt. %) Example 29 Core Methyl 1.0 588 60 60 0.06 C-1
100.0 588 60 120 49.79 particles 7 triethoxysilane Example 30 Core
Methyl hydrogen 1.0 588 60 30 0.26 C-1 10.0 392 40 180 9.03
particles 8 polysiloxane Example 31 Core Phenyl 2.0 392 40 60 0.70
C-1 50.0 392 40 120 4.68 particles 9 triethoxysilane Example 32
Core Methyl 1.5 392 40 60 0.10 C-2 10.0 392 40 180 7.37 particles
10 triethoxysilane Example 33 Core .gamma.-aminopropyl 0.5 588 60
20 0.08 C-2 150.0 588 60 60 49.06 particles 13 triethoxysilane
Example 34 Core Dimethyl 1.0 735 75 30 0.19 C-1 10.0 392 40 120
9.02 particles 14 dimethoxysilane Example 35 Core Polyvinyl 1.0 294
30 20 0.54 C-2 2.0 392 40 120 1.55 particles 15 alcohol Example 36
Core Isopropyl 2.0 441 45 30 1.47 C-1 5.0 392 40 60 4.70 particles
16 triisostearoyl titanate Comparative Core -- -- -- -- -- -- C-1
10.0 588 60 60 9.01 Example 9 particles 8 Comparative Core Methyl
1.0 588 60 60 0.06 C-1 750.0 588 60 60 88.02 Example 10 particles 8
triethoxysilane Comparative Core Methyl 1.0 588 60 60 0.06 C-1 10.0
588 60 60 9.01 Example 11 particles 11 triethoxysilane Comparative
Core Methyl 1.0 588 60 60 0.06 C-1 10.0 588 60 60 9.01 Example 12
particles 12 triethoxysilane
TABLE 14 Properties of black composite particles Black Average BET
specific Volume Light pigment Examples and particle surface area
Blackness Tinting resistivity Surface resistance desorption
Comparative diameter value (L* value) strength Repose angle value
activity (.DELTA.E* value) percentage Examples (.mu.m) (m.sup.2 /g)
(-) (%) (.degree.) (.OMEGA. .multidot. cm) (%) (-) (%) Example 29
3.919 132.8 17.03 208 33 2.3 .times. 10.sup.4 0.47 1.65 7.1 Example
30 0.604 6.8 19.59 129 36 1.6 .times. 10.sup.5 0.88 2.31 6.3
Example 31 0.060 25.6 20.11 127 38 .sup. 6.8 .times. 10.sup.10 1.04
2.48 5.6 Example 32 0.141 21.3 19.62 126 39 .sup. 6.5 .times.
10.sup.10 0.92 2.44 5.9 Example 33 3.922 87.3 16.93 188 32 .sup.
2.1 .times. 10.sup.11 0.41 1.72 4.9 Example 34 0.611 5.6 19.48 130
35 3.6 .times. 10.sup.5 0.76 2.00 3.2 Example 35 0.061 26.6 21.82
116 41 .sup. 1.8 .times. 10.sup.10 1.59 3.17 1.6 Example 36 0.143
19.8 17.94 175 34 6.9 .times. 10.sup.4 0.55 1.69 4.3 Comparative
0.603 7.7 21.44 100 48 6.3 .times. 10.sup.5 2.18 6.16 66.1 Example
9 Comparative 0.616 121.3 16.93 194 53 5.3 .times. 10.sup.2 2.69
6.13 31.3 Example 10 Comparative 0.324 6.3 18.22 127 46 2.1 .times.
10.sup.4 2.24 5.38 6.1 Example 11 Comparative 0.231 14.8 17.38 130
48 1.6 .times. 10.sup.4 2.35 5.72 6.2 Example 12
TABLE 15 Production of paint Black composite particles Black
pigments Properties of coating film Amount Amount Properties of
paint Blackness Light resistance added added Viscosity Storage
stability 60.degree. gloss (L* value) (.DELTA.E* value) Examples
Kind (wt. part) Kind (wt. part) (cP) (-) (%) (-) (-) Example 37
Example 29 12.2 -- -- 1,280 0.73 94 17.29 1.96 Example 38 Example
30 12.2 -- -- 1,162 0.90 93 19.92 2.51 Example 39 Example 31 12.2
-- -- 1,068 0.96 91 20.45 2.69 Example 40 Example 32 12.2 -- -- 962
0.81 90 19.83 2.65 Example 41 Example 33 12.2 -- -- 983 0.65 98
17.44 1.97 Example 42 Example 34 12.2 -- -- 1,024 0.86 98 19.65
2.26 Example 43 Example 35 12.2 -- -- 1,380 1.31 91 22.00 3.43
Example 44 Example 36 12.2 -- -- 1,260 0.72 96 18.32 1.91
TABLE 16 Production of paint Particles Black pigments Properties of
coating film Amount Amount Properties of paint Blackness Light
resistance Comparative added added Viscosity Storage stability
60.degree. gloss (L* value) (.DELTA.E* value) Examples Kind (wt.
part) Kind (wt. part) (cP) (-) (%) (-) (-) Comparative -- -- C-1
12.2 25,600 2.16 63 16.95 9.16 Example 13 Comparative -- -- C-2
12.2 41,300 2.38 60 16.87 9.83 Example 14 Comparative Core 6.1 C-1
6.1 14,200 1.86 66 21.86 6.63 Example 15 particles 7 Comparative
Core 11.1 C-1 1.1 4,360 1.73 72 26.98 5.97 Example 16 particles 8
Comparative Core 11.6 C-1 0.6 5,296 1.71 73 27.82 6.54 Example 17
particles 9 Comparative Core 11.1 C-2 1.1 5,672 1.83 70 27.14 7.48
Example 18 particles 10 Comparative Comparative 12.2 -- -- 12,820
1.89 56 21.79 6.45 Example 19 Example 9 Comparative Comparative
12.2 -- -- 26,380 2.04 68 17.05 6.50 Example 20 Example 10
Comparative Comparative 12.2 -- -- 988 1.75 92 18.57 5.72 Example
21 Example 11 Comparative Comparative 12.2 -- -- 1,024 1.88 91
17.66 6.11 Example 22 Example 12
TABLE 17 Production of water-based paint Black composite particles
Black pigments Properties of coating film Amount Amount Properties
of paint Blackness Light resistance added added Viscosity Storage
stability 60.degree. gloss (L* value) (.DELTA.E* value) Examples
Kind (wt. part) Kind (wt. part) (cP) (-) (%) (-) (-) Example 45
Example 29 12.4 -- -- 2,836 0.72 90 17.33 1.91 Example 46 Example
30 12.4 -- -- 3,168 0.89 89 19.86 2.42 Example 47 Example 31 12.4
-- -- 3,196 0.96 86 20.56 2.66 Example 48 Example 32 12.4 -- --
2,834 0.80 89 19.88 2.58 Example 49 Example 33 12.4 -- -- 2,381
0.64 91 17.57 1.94 Example 50 Example 34 12.4 -- -- 3,122 0.84 90
19.72 2.21 Example 51 Example 35 12.4 -- -- 2,816 1.29 88 22.04
3.40 Example 52 Example 36 12.4 -- -- 2,318 0.70 95 18.41 1.88
TABLE 18 Production of water-based paint Particles Black pigments
Properties of coating film Amount Amount Properties of paint
Blackness Light resistance Comparative added added Viscosity
Storage stability 60.degree. gloss (L* value) (.DELTA.E* value)
Examples Kind (wt. part) Kind (wt. part) (cP) (-) (%) (-) (-)
Comparative -- -- C-1 12.4 35,820 2.04 62 17.01 9.13 Example 23
Comparative -- -- C-2 12.4 56,890 2.30 59 16.92 9.73 Example 24
Comparative Core 6.2 C-1 6.2 19,565 1.81 64 21.93 6.60 Example 25
particles 7 Comparative Core 11.3 C-1 1.1 6,240 1.71 70 27.14 5.94
Example 26 particles 8 Comparative Core 11.8 C-1 0.6 5,808 1.65 70
28.02 6.49 Example 27 particles 9 Comparative Core 11.3 C-2 1.1
6,816 1.76 68 27.37 7.43 Example 28 particles 10 Comparative
Comparative 12.4 -- -- 15,652 1.81 48 21.95 6.41 Example 29 Example
9 Comparative Comparative 12.4 -- -- 39,260 2.00 65 17.11 6.47
Example 30 Example 10 Comparative Comparative 12.4 -- -- 923 1.72
90 18.63 5.66 Example 31 Example 11 Comparative Comparative 12.4 --
-- 947 1.86 88 17.78 6.02 Example 32 Example 12
TABLE 19 Production of resin composition Properties of resin
composition Black composite Percentage of surface area of
deteriorated and particles Black pigments discolored portion when
heated at 190.degree. C. Amount Amount Dispersing Blackness Light
resistance (%) added added condition (L* value) (.DELTA.E* value)
After After After Examples Kind (wt. part) Kind (wt. part) (-) (-)
(-) 30 minutes 60 minutes 120 minutes Example 53 Example 29 5.0 --
-- 5 17.69 1.96 0 0 0 Example 54 Example 30 5.0 -- -- 5 19.89 2.56
0 0 5 Example 55 Example 31 5.0 -- -- 5 20.46 2.68 0 5 5 Example 56
Example 32 5.0 -- -- 4 19.39 2.76 0 5 5 Example 57 Example 33 5.0
-- -- 5 17.69 1.96 0 0 0 Example 58 Example 34 5.0 -- -- 5 19.73
2.33 0 0 0 Example 59 Example 35 5.0 -- -- 4 22.25 3.41 0 5 10
Example 60 Example 36 5.0 -- -- 5 18.38 2.02 0 0 5
TABLE 20 Production of resin composition Percentage of surface area
of deteriorated and Particles Black pigments discolored portion
when heated at 190.degree. C. Amount Amount Dispersing Blackness
Light resistance (%) Comparative added added condition (L* value)
(.DELTA.E* value) After After After Examples Kind (wt. part) Kind
(wt. part) (-) (-) (-) 30 minutes 60 minutes 120 minutes
Comparative -- -- C-1 5.0 1 17.18 10.17 10 20 35 Example 33
Comparative -- -- C-2 5.0 1 17.03 10.44 15 30 40 Example 34
Comparative Core 2.5 C-1 2.5 1 21.94 7.26 10 10 30 Example 35
particles 7 Comparative Core 4.5 C-2 0.5 2 27.25 6.12 10 15 20
Example 36 particles 8 Comparative Core 4.8 C-1 0.2 2 28.17 7.15 10
20 20 Example 37 particles 9 Comparative Core 4.5 C-2 0.5 2 27.49
7.84 10 25 30 Example 38 particles 10 Comparative Comparative 5.0
-- -- 1 21.76 7.16 10 10 25 Example 39 Example 9 Comparative
Comparative 5.0 -- -- 2 17.38 6.93 5 10 20 Example 40 Example 10
Comparative Comparative 5.0 -- -- 4 18.60 6.35 0 5 15 Example 41
Example 11 Comparative Comparative 5.0 -- -- 4 17.66 6.98 0 5 15
Example 42 Example 12
TABLE 21 Properties of white inorganic particles BET Ultraviolet
specific light - Average surface shielding Light particle area Hue
Refractive property resistance Kind of core diameter value L* value
a* value b* value C* value index (360 nm) (.DELTA.E* value)
particles Kind Shape (.mu.m) (m.sup.2 /g) (-) (-) (-) (-) (-) (%)
(-) Core Titanium Granular 0.253 10.3 96.63 -0.58 -0.69 0.90 2.71
65 6.15 particles 17 oxide Core Titanium Granular 0.053 61.2 95.13
0.13 0.21 0.25 2.71 71 10.16 particles 18 oxide Core Zinc oxide
Granular 0.183 18.3 90.27 -2.14 4.13 4.65 2.03 80 5.86 particles
19
TABLE 22 Surface-treating step Kind of Additives Coating Material
Core core Calculated Amount Calculated Amount particles particles
Kind as (wt. %) Kind as (wt. %) Core Core Sodium Al 1.0 A Al 0.98
particles 20 particles 17 aluminate Core Core Sodium Al 1.5 A Al
1.48 particles 21 particles 18 aluminate SiO.sub.2 1.0 S SiO.sub.2
0.99 Water glass #3 Core Core Water SiO.sub.2 1.0 S SiO.sub.2 0.98
particles 22 particles 19 glass #3
TABLE 23 Properties of surface-treated white inorganic particles
Average particle BET specific Hue Light resistance Kind of core
diameter surface area value L* value a* value b* value C* value
Refractive index (.DELTA.E* value) particles (.mu.m) (m.sup.2 /g)
(-) (-) (-) (-) (-) (-) Core 0.254 12.1 96.49 -0.46 -0.54 0.71 2.71
5.86 particles 20 Core 0.054 60.8 95.16 0.14 0.20 0.24 2.71 8.36
particles 21 Core 0.184 18.0 89.52 -1.91 5.18 5.52 2.00 5.14
particles 22
TABLE 24 Production of composite particles Coating step with gluing
agent Coating step with black pigments Coating Amount amount Black
pigments coated Examples Additives (calcu- Amount (calcu- and
Amount Edge Runner Treatment lated added Edge Runner Treatment
lated Comparative Kind of core (wt. Linear Load Time as C) (wt.
Linear Load Time as C) Examples particles Kind part) (N/cm) (Kg/cm)
(min) (wt. %) Kind part) (N/cm) (Kg/cm) (min) (wt. %) Example 61
Core Methyl 1.0 588 60 30 0.06 C-1 50.0 392 40 60 33.18 particles
17 triethoxysilane Example 62 Core .gamma.-aminopropyl 1.5 392 40
60 0.24 C-2 100.0 588 60 30 40.87 particles 18 triethoxysilane
Example 63 Core Polyvinyl 1.0 588 60 20 0.54 C-1 50.0 392 40 60
33.09 particles 19 alcohol Example 64 Core Isopropyl 1.0 392 40 30
0.74 C-2 75.0 392 40 120 35.02 particles 20 triisostearoyl titanate
Example 65 Core Methyl hydrogen 2.0 588 60 20 0.53 C-1 10.0 588 60
60 9.05 particles 21 polysiloxane Example 66 Core Methyl hydrogen
1.0 392 40 20 0.26 C-2 30.0 392 40 180 18.78 particles 22
polysiloxane Comparative Core -- -- -- -- -- -- C-1 50.0 588 60 60
33.12 Example 43 particles 17 Comparative Core Methyl 1.0 588 60 30
0.06 -- -- -- -- -- -- Example 44 particles 17 triethoxysilane
Comparative Core Methyl 1.0 588 60 60 0.06 C-1 750.0 588 60 60
88.14 Example 45 particles 17 triethoxysilane Comparative Core
Methyl 1.0 588 60 60 0.06 C-1 50.0 588 60 60 33.11 Example 46
particles 11 triethoxysilane Comparative Core Methyl 1.0 588 60 60
0.06 C-1 50.0 588 60 60 33.15 Example 47 particles 12
triethoxysilane
TABLE 25 Properties of composite particles Ultraviolet light-
Average BET specific Volume shielding Black pigment Examples and
particle surface area Tinting Repose resistivity property Surface
Light resistance desorption Comparative diameter value L* value
strength angle value (360 nm) activity (.DELTA.E* value) percentage
Examples (.mu.m) (m.sup.2 /g) (-) (%) (.degree.) (.OMEGA.
.multidot. cm) (%) (%) (-) (%) Example 61 0.255 14.1 25.85 183 38
8.6 .times. 10.sup.4 93 0.77 2.23 7.6 Example 62 0.057 59.3 18.36
192 36 .sup. 2.3 .times. 10.sup.11 92 0.63 2.18 8.3 Example 63
0.185 21.3 19.14 186 37 7.6 .times. 10.sup.4 93 0.74 1.91 7.8
Example 64 0.257 14.6 24.17 184 36 .sup. 1.2 .times. 10.sup.11 90
0.56 1.98 4.7 Example 65 0.055 65.4 21.62 129 38 2.1 .times.
10.sup.5 91 0.95 2.20 2.6 Example 66 0.186 18.6 19.98 176 37 .sup.
6.3 .times. 10.sup.10 90 0.72 1.89 3.5 Comparative 0.253 18.3 27.33
100 48 1.9 .times. 10.sup.5 68 2.21 6.02 64.3 Example 43
Comparative 0.253 9.6 96.78 100 49 5.7 .times. 10.sup.9 66 2.65
6.11 -- Example 44 Comparative 0.269 68.3 19.60 194 54 8.9 .times.
10.sup.2 90 2.28 5.83 33.4 Example 45 Comparative 0.325 12.2 17.76
131 48 8.7 .times. 10.sup.3 76 1.83 5.14 7.6 Example 46 Comparative
0.232 17.9 17.14 136 50 7.5 .times. 10.sup.3 79 1.88 5.49 7.5
Example 47
TABLE 26 Production of paint Composite particles Black pigments
Properties of paint Properties of coating film Amount Amount
Storage Blackness Light resistance added added Viscosity stability
60.degree. gloss (L* value) (.DELTA.E* value) Examples Kind (wt.
part) Kind (wt . part) (cP) (-) (%) (-) (-) Example 67 Example 61
12.2 -- -- 1,168 0.98 94 26.32 2.38 Example 68 Example 62 12.2 --
-- 983 0.91 96 18.61 2.31 Example 69 Example 63 12.2 -- -- 868 1.04
95 19.31 2.12 Example 70 Example 64 12.2 -- -- 1,024 0.95 99 24.33
2.16 Example 71 Example 65 12.2 -- -- 1,152 0.90 103 21.75 2.38
Example 72 Example 66 12.2 -- -- 1,216 1.02 100 20.34 2.01
TABLE 27 Production of paint Particles Black pigments Properties of
paint Properties of coating film Amount Amount Storage Light
resistance Comparative added added Viscosity stability 60.degree.
gloss L* value (.DELTA.E* value) Examples Kind (wt. part) Kind (wt
. part) (cP) (-) (%) (-) (-) Comparative Core 8.1 C-1 4.1 1,234
1.83 68 30.19 6.26 Example 48 particles 17 Comparative Core 6.1 C-2
6.1 1,381 1.82 71 25.46 10.37 Example 49 particles 18 Comparative
Core 8.1 C-1 4.1 1,414 2.03 65 27.08 6.11 Example 50 particles 19
Comparative Comparative 12.2 -- -- 12,860 1.81 66 28.38 6.35
Example 51 Example 43 Comparative Comparative 12.2 -- -- 1,382 1.85
84 96.89 6.42 Example 52 Example 44 Comparative Comparative 12.2 --
-- 25,600 2.01 70 20.72 6.01 Example 53 Example 45 Comparative
Comparative 12.2 -- -- 964 1.78 79 18.14 5.40 Example 54 Example 46
Comparative Comparative 12.2 -- -- 988 1.94 76 17.57 5.74 Example
55 Example 47
TABLE 28 Production of water-based paint Composite particles Black
pigments Properties of paint Properties of coating film Amount
Amount Storage Light resistance added added Viscosity stability
60.degree. gloss L* value (.DELTA.E* value) Examples Kind (wt.
part) Kind (wt. part) (cP) (-) (%) (-) (-) Example 73 Example 61
12.4 -- -- 2,380 0.97 89 26.61 2.41 Example 74 Example 62 12.4 --
-- 3,162 0.90 92 18.80 2.33 Example 75 Example 63 12.4 -- -- 2,862
1.04 90 19.51 2.09 Example 76 Example 64 12.4 -- -- 2,562 0.94 94
24.42 2.18 Example 77 Example 65 12.4 -- -- 2,483 0.90 100 21.83
2.35 Example 78 Example 66 12.4 -- -- 2,616 1.03 95 20.32 1.98
TABLE 29 Production of water-based paint Particles Black pigments
Properties of paint Properties of coating film Amount Amount
Storage Light resistance Comparative added added Viscosity
stability 60.degree. gloss L* value (.DELTA.E* value) Examples Kind
(wt. part) Kind (wt. part) (cP) (-) (%) (-) (-) Comparative Core
8.3 C-1 4.1 15,652 1.81 65 30.48 6.30 Example 56 particles 17
Comparative Core 6.2 C-2 6.2 18,363 1.77 68 25.77 10.41 Example 57
particles 18 Comparative Core 8.3 C-1 4.1 16,148 2.00 62 27.36 6.09
Example 58 particles 19 Comparative Comparative 12.4 -- -- 15,034
1.82 64 28.59 6.38 Example 59 Example 43 Comparative Comparative
12.4 -- -- 2,362 1.85 81 96.80 6.41 Example 60 Example 44
Comparative Comparative 12.4 -- -- 2,232 1.99 69 20.84 5.95 Example
61 Example 45 Comparative Comparative 12.4 -- -- 906 1.76 75 18.23
5.42 Example 62 Example 46 Comparative Comparative 12.4 -- -- 914
1.92 71 17.59 5.73 Example 63 Example 47
TABLE 30 Properties of resin composition Production of resin
composition Percentage of surface area of deteriorated and
Composite particles Black pigments discolored portion when heated
at 190.degree. C. Amount Amount Dispersing Light resistance (%)
added added condition L* value (.DELTA.E* value) After After After
Examples Kind (wt. part) Kind (wt. part) (-) (-) (-) 30 minutes 60
minutes 120 minutes Example 79 Example 61 5.0 -- -- 5 26.92 2.48 0
5 5 Example 80 Example 62 5.0 -- -- 5 19.03 2.43 0 0 5 Example 81
Example 63 5.0 -- -- 5 19.72 2.18 0 5 5 Example 82 Example 64 5.0
-- -- 5 25.00 2.26 0 0 5 Example 83 Example 65 5.0 -- -- 5 22.13
2.41 0 5 10 Example 84 Example 66 5.0 -- -- 5 20.66 2.05 0 5 5
TABLE 31 Properties of resin composition Production of resin
composition Percentage of surface area of deteriorated and
Particles Black pigments discolored portion when heated at
190.degree. C. Amount Amount Dispersing Light resistance (%)
Comparative added added condition L* value (.DELTA.E* value) After
After After Examples Kind (wt. part) Kind (wt. part) (-) (-) (-) 30
minutes 60 minutes 120 minutes Comparative Core 3.3 C-1 1.7 2 30.51
6.75 5 15 35 Example 64 particles 17 Comparative Core 2.5 C-2 2.5 1
25.79 10.83 10 20 40 Example 65 particles 18 Comparative Core 3.3
C-1 1.7 2 27.43 6.47 5 15 30 Example 66 particles 19 Comparative
Comparative 5.0 -- -- 1 28.66 6.61 5 15 35 Example 67 Example 43
Comparative Comparative 5.0 -- -- 3 96.74 6.92 5 10 25 Example 68
Example 44 Comparative Comparative 5.0 -- -- 2 20.87 6.32 5 10 20
Example 69 Example 45 Comparative Comparative 5.0 -- -- 2 18.26
5.65 0 5 20 Example 70 Example 46 Comparative Comparative 5.0 -- --
2 17.65 6.03 0 10 20 Example 71 Example 47
* * * * *